diff --git a/examples/src/aws_kms_discovery_keyring_example.py b/examples/src/aws_kms_discovery_keyring_example.py
index 3baa668d4..ba02b62a7 100644
--- a/examples/src/aws_kms_discovery_keyring_example.py
+++ b/examples/src/aws_kms_discovery_keyring_example.py
@@ -33,14 +33,14 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateAwsKmsDiscoveryKeyringInput,
     CreateAwsKmsKeyringInput,
     DiscoveryFilter,
 )
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_discovery_multi_keyring_example.py b/examples/src/aws_kms_discovery_multi_keyring_example.py
index d07d499b2..5dd85f99c 100644
--- a/examples/src/aws_kms_discovery_multi_keyring_example.py
+++ b/examples/src/aws_kms_discovery_multi_keyring_example.py
@@ -30,14 +30,14 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateAwsKmsDiscoveryMultiKeyringInput,
     CreateAwsKmsKeyringInput,
     DiscoveryFilter,
 )
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_keyring_example.py b/examples/src/aws_kms_keyring_example.py
index dc18dadc2..8590b35ef 100644
--- a/examples/src/aws_kms_keyring_example.py
+++ b/examples/src/aws_kms_keyring_example.py
@@ -18,10 +18,10 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_mrk_discovery_keyring_example.py b/examples/src/aws_kms_mrk_discovery_keyring_example.py
index a93552532..a88e1ae20 100644
--- a/examples/src/aws_kms_mrk_discovery_keyring_example.py
+++ b/examples/src/aws_kms_mrk_discovery_keyring_example.py
@@ -35,14 +35,14 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateAwsKmsMrkDiscoveryKeyringInput,
     CreateAwsKmsMrkKeyringInput,
     DiscoveryFilter,
 )
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_mrk_discovery_multi_keyring_example.py b/examples/src/aws_kms_mrk_discovery_multi_keyring_example.py
index 958683a19..26412e2b2 100644
--- a/examples/src/aws_kms_mrk_discovery_multi_keyring_example.py
+++ b/examples/src/aws_kms_mrk_discovery_multi_keyring_example.py
@@ -37,14 +37,14 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateAwsKmsMrkDiscoveryMultiKeyringInput,
     CreateAwsKmsMrkKeyringInput,
     DiscoveryFilter,
 )
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_mrk_keyring_example.py b/examples/src/aws_kms_mrk_keyring_example.py
index 8611a6120..1cadfec45 100644
--- a/examples/src/aws_kms_mrk_keyring_example.py
+++ b/examples/src/aws_kms_mrk_keyring_example.py
@@ -22,10 +22,10 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsMrkKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsMrkKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_mrk_multi_keyring_example.py b/examples/src/aws_kms_mrk_multi_keyring_example.py
index 9c32affb8..d9514d961 100644
--- a/examples/src/aws_kms_mrk_multi_keyring_example.py
+++ b/examples/src/aws_kms_mrk_multi_keyring_example.py
@@ -28,10 +28,13 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsMrkKeyringInput, CreateAwsKmsMrkMultiKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
+    CreateAwsKmsMrkKeyringInput,
+    CreateAwsKmsMrkMultiKeyringInput,
+)
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_multi_keyring_example.py b/examples/src/aws_kms_multi_keyring_example.py
index 4e74eafc8..69928ccd7 100644
--- a/examples/src/aws_kms_multi_keyring_example.py
+++ b/examples/src/aws_kms_multi_keyring_example.py
@@ -38,10 +38,10 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput, CreateAwsKmsMultiKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput, CreateAwsKmsMultiKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/aws_kms_rsa_keyring_example.py b/examples/src/aws_kms_rsa_keyring_example.py
index e86ea6973..4750660eb 100644
--- a/examples/src/aws_kms_rsa_keyring_example.py
+++ b/examples/src/aws_kms_rsa_keyring_example.py
@@ -15,10 +15,10 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsRsaKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsRsaKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/branch_key_id_supplier_example.py b/examples/src/branch_key_id_supplier_example.py
index b25d9abeb..a14e8eae3 100644
--- a/examples/src/branch_key_id_supplier_example.py
+++ b/examples/src/branch_key_id_supplier_example.py
@@ -2,8 +2,8 @@
 # SPDX-License-Identifier: Apache-2.0
 """Example implementation of a branch key ID supplier."""
 
-from aws_cryptographic_materialproviders.mpl.models import GetBranchKeyIdInput, GetBranchKeyIdOutput
-from aws_cryptographic_materialproviders.mpl.references import IBranchKeyIdSupplier
+from aws_cryptographic_material_providers.mpl.models import GetBranchKeyIdInput, GetBranchKeyIdOutput
+from aws_cryptographic_material_providers.mpl.references import IBranchKeyIdSupplier
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 
diff --git a/examples/src/custom_mpl_cmm_example.py b/examples/src/custom_mpl_cmm_example.py
index 544ca5f00..b9a8f043f 100644
--- a/examples/src/custom_mpl_cmm_example.py
+++ b/examples/src/custom_mpl_cmm_example.py
@@ -23,13 +23,13 @@
 https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/concepts.html#crypt-materials-manager
 """
 
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateDefaultCryptographicMaterialsManagerInput,
     SignatureAlgorithmNone,
 )
-from aws_cryptographic_materialproviders.mpl.references import ICryptographicMaterialsManager, IKeyring
+from aws_cryptographic_material_providers.mpl.references import ICryptographicMaterialsManager, IKeyring
 
 import aws_encryption_sdk
 from aws_encryption_sdk import CommitmentPolicy
@@ -65,10 +65,10 @@ def __init__(self, keyring: IKeyring, cmm: ICryptographicMaterialsManager = None
     def get_encryption_materials(self, param):
         """Provides encryption materials appropriate for the request for the custom CMM.
 
-        :param aws_cryptographic_materialproviders.mpl.models.GetEncryptionMaterialsInput param: Input object to
+        :param aws_cryptographic_material_providers.mpl.models.GetEncryptionMaterialsInput param: Input object to
         provide to a crypto material manager's `get_encryption_materials` method.
         :returns: Encryption materials output
-        :rtype: aws_cryptographic_materialproviders.mpl.models.GetEncryptionMaterialsOutput
+        :rtype: aws_cryptographic_material_providers.mpl.models.GetEncryptionMaterialsOutput
         """
         materials = self.underlying_cmm.get_encryption_materials(param)
         if isinstance(materials.encryption_materials.algorithm_suite.signature, SignatureAlgorithmNone):
@@ -81,10 +81,10 @@ def get_encryption_materials(self, param):
     def decrypt_materials(self, param):
         """Provides decryption materials appropriate for the request for the custom CMM.
 
-        :param aws_cryptographic_materialproviders.mpl.models.DecryptMaterialsInput param: Input object to provide
+        :param aws_cryptographic_material_providers.mpl.models.DecryptMaterialsInput param: Input object to provide
         to a crypto material manager's `decrypt_materials` method.
         :returns: Decryption materials output
-        :rtype: aws_cryptographic_materialproviders.mpl.models.GetDecryptionMaterialsOutput
+        :rtype: aws_cryptographic_material_providers.mpl.models.GetDecryptionMaterialsOutput
         """
         materials = self.underlying_cmm.decrypt_materials(param)
         if isinstance(materials.decryption_materials.algorithm_suite.signature, SignatureAlgorithmNone):
diff --git a/examples/src/default_cryptographic_materials_manager_example.py b/examples/src/default_cryptographic_materials_manager_example.py
index 091e79ada..e60b1cea7 100644
--- a/examples/src/default_cryptographic_materials_manager_example.py
+++ b/examples/src/default_cryptographic_materials_manager_example.py
@@ -18,13 +18,13 @@
 https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/concepts.html#crypt-materials-manager
 """
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateAwsKmsKeyringInput,
     CreateDefaultCryptographicMaterialsManagerInput,
 )
-from aws_cryptographic_materialproviders.mpl.references import ICryptographicMaterialsManager, IKeyring
+from aws_cryptographic_material_providers.mpl.references import ICryptographicMaterialsManager, IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/file_streaming_example.py b/examples/src/file_streaming_example.py
index debbb6859..56953f667 100644
--- a/examples/src/file_streaming_example.py
+++ b/examples/src/file_streaming_example.py
@@ -25,10 +25,10 @@
 import filecmp
 import secrets
 
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/hierarchical_keyring_example.py b/examples/src/hierarchical_keyring_example.py
index 92efa2865..a325491e3 100644
--- a/examples/src/hierarchical_keyring_example.py
+++ b/examples/src/hierarchical_keyring_example.py
@@ -35,17 +35,17 @@
 import boto3
 # Ignore missing MPL for pylint, but the MPL is required for this example
 # noqa pylint: disable=import-error
-from aws_cryptographic_materialproviders.keystore import KeyStore
-from aws_cryptographic_materialproviders.keystore.config import KeyStoreConfig
-from aws_cryptographic_materialproviders.keystore.models import CreateKeyInput, KMSConfigurationKmsKeyArn
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.keystore import KeyStore
+from aws_cryptographic_material_providers.keystore.config import KeyStoreConfig
+from aws_cryptographic_material_providers.keystore.models import CreateKeyInput, KMSConfigurationKmsKeyArn
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CacheTypeDefault,
     CreateAwsKmsHierarchicalKeyringInput,
     DefaultCache,
 )
-from aws_cryptographic_materialproviders.mpl.references import IBranchKeyIdSupplier, IKeyring
+from aws_cryptographic_material_providers.mpl.references import IBranchKeyIdSupplier, IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/migration/migration_aws_kms_key_example.py b/examples/src/migration/migration_aws_kms_key_example.py
index e0a577d20..c46c6f1c9 100644
--- a/examples/src/migration/migration_aws_kms_key_example.py
+++ b/examples/src/migration/migration_aws_kms_key_example.py
@@ -21,10 +21,10 @@
 https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/use-kms-keyring.html
 """
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/migration/migration_raw_aes_key_example.py b/examples/src/migration/migration_raw_aes_key_example.py
index 4bd15d1f9..c00ec489e 100644
--- a/examples/src/migration/migration_raw_aes_key_example.py
+++ b/examples/src/migration/migration_raw_aes_key_example.py
@@ -26,10 +26,10 @@
 """
 import secrets
 
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/migration/migration_raw_rsa_key_example.py b/examples/src/migration/migration_raw_rsa_key_example.py
index 22c9512ec..8d4d3f322 100644
--- a/examples/src/migration/migration_raw_rsa_key_example.py
+++ b/examples/src/migration/migration_raw_rsa_key_example.py
@@ -28,10 +28,10 @@
 For more information on how to use Raw RSA keyrings, see
 https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/use-raw-rsa-keyring.html
 """
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from cryptography.hazmat.backends import default_backend as crypto_default_backend
 from cryptography.hazmat.primitives import serialization as crypto_serialization
 from cryptography.hazmat.primitives.asymmetric import rsa
diff --git a/examples/src/migration/migration_set_commitment_policy_example.py b/examples/src/migration/migration_set_commitment_policy_example.py
index 81506e710..b698fd3ab 100644
--- a/examples/src/migration/migration_set_commitment_policy_example.py
+++ b/examples/src/migration/migration_set_commitment_policy_example.py
@@ -21,10 +21,10 @@
 """
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/multi_keyring_example.py b/examples/src/multi_keyring_example.py
index f55b2aeca..2465c7c04 100644
--- a/examples/src/multi_keyring_example.py
+++ b/examples/src/multi_keyring_example.py
@@ -39,15 +39,15 @@
 import secrets
 
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     AesWrappingAlg,
     CreateAwsKmsKeyringInput,
     CreateMultiKeyringInput,
     CreateRawAesKeyringInput,
 )
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/multithreading/__init__.py b/examples/src/multithreading/__init__.py
index 4fdad58fd..6ac3d9a33 100644
--- a/examples/src/multithreading/__init__.py
+++ b/examples/src/multithreading/__init__.py
@@ -3,7 +3,7 @@
 """init file for multi-threading examples."""
 import time
 
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/multithreading/raw_aes_keyring.py b/examples/src/multithreading/raw_aes_keyring.py
index 42a391344..65e4627b1 100644
--- a/examples/src/multithreading/raw_aes_keyring.py
+++ b/examples/src/multithreading/raw_aes_keyring.py
@@ -4,10 +4,10 @@
 
 import secrets
 
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 
 
 def create_keyring():
diff --git a/examples/src/multithreading/raw_rsa_keyring.py b/examples/src/multithreading/raw_rsa_keyring.py
index 77d26f2fc..06d2fe679 100644
--- a/examples/src/multithreading/raw_rsa_keyring.py
+++ b/examples/src/multithreading/raw_rsa_keyring.py
@@ -1,10 +1,10 @@
 # Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
 # SPDX-License-Identifier: Apache-2.0
 """This file contains methods to use for testing multi-threading for Raw RSA keyring."""
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from cryptography.hazmat.backends import default_backend as crypto_default_backend
 from cryptography.hazmat.primitives import serialization as crypto_serialization
 from cryptography.hazmat.primitives.asymmetric import rsa
diff --git a/examples/src/raw_aes_keyring_example.py b/examples/src/raw_aes_keyring_example.py
index a28c350ff..0e0b53491 100644
--- a/examples/src/raw_aes_keyring_example.py
+++ b/examples/src/raw_aes_keyring_example.py
@@ -23,10 +23,10 @@
 """
 import secrets
 
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/src/raw_rsa_keyring_example.py b/examples/src/raw_rsa_keyring_example.py
index 22101bb57..e59a9581c 100644
--- a/examples/src/raw_rsa_keyring_example.py
+++ b/examples/src/raw_rsa_keyring_example.py
@@ -33,10 +33,10 @@
 https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/use-raw-rsa-keyring.html
 """
 
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from cryptography.hazmat.backends import default_backend as crypto_default_backend
 from cryptography.hazmat.primitives import serialization as crypto_serialization
 from cryptography.hazmat.primitives.asymmetric import rsa
diff --git a/examples/src/required_encryption_context_cmm.py b/examples/src/required_encryption_context_cmm.py
index edbb3f414..8edf7545e 100644
--- a/examples/src/required_encryption_context_cmm.py
+++ b/examples/src/required_encryption_context_cmm.py
@@ -10,14 +10,14 @@
 import boto3
 # Ignore missing MPL for pylint, but the MPL is required for this example
 # noqa pylint: disable=import-error
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateAwsKmsKeyringInput,
     CreateDefaultCryptographicMaterialsManagerInput,
     CreateRequiredEncryptionContextCMMInput,
 )
-from aws_cryptographic_materialproviders.mpl.references import ICryptographicMaterialsManager, IKeyring
+from aws_cryptographic_material_providers.mpl.references import ICryptographicMaterialsManager, IKeyring
 from typing import Dict, List  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
@@ -142,7 +142,7 @@ def encrypt_and_decrypt_with_keyring(
     try:
         plaintext_bytes_a, _ = client.decrypt(
             source=ciphertext,
-            materials_manager=required_ec_cmm,
+            materials_manager=underlying_cmm,
             # No reproduced encryption context for required EC CMM-produced message makes decryption fail.
         )
         raise Exception("If this exception is raised, decryption somehow succeeded!")
diff --git a/examples/src/set_encryption_algorithm_suite_example.py b/examples/src/set_encryption_algorithm_suite_example.py
index 95c7a0938..f6df411aa 100644
--- a/examples/src/set_encryption_algorithm_suite_example.py
+++ b/examples/src/set_encryption_algorithm_suite_example.py
@@ -39,10 +39,10 @@
 """
 import secrets
 
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from typing import Dict  # noqa pylint: disable=wrong-import-order
 
 import aws_encryption_sdk
diff --git a/examples/test/test_i_custom_mpl_cmm_example.py b/examples/test/test_i_custom_mpl_cmm_example.py
index d98b6b6b9..6791914c4 100644
--- a/examples/test/test_i_custom_mpl_cmm_example.py
+++ b/examples/test/test_i_custom_mpl_cmm_example.py
@@ -3,10 +3,10 @@
 """Test suite for encryption and decryption using custom CMM."""
 import boto3
 import pytest
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 
 from ..src.custom_mpl_cmm_example import MPLCustomSigningSuiteOnlyCMM, encrypt_decrypt_with_cmm
 
diff --git a/performance_tests/requirements_mpl.txt b/performance_tests/requirements_mpl.txt
index d9744a723..9d72dfb8e 100644
--- a/performance_tests/requirements_mpl.txt
+++ b/performance_tests/requirements_mpl.txt
@@ -1 +1 @@
-aws-cryptographic-materialproviders @ git+https://github.com/aws/aws-cryptographic-material-providers-library.git@python-with-dafny-code#subdirectory=AwsCryptographicMaterialProviders/runtimes/python
\ No newline at end of file
+aws-cryptographic-material-providers @ git+https://github.com/aws/aws-cryptographic-material-providers-library.git@python-main-with-dafny-code#subdirectory=AwsCryptographicMaterialProviders/runtimes/python
diff --git a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/aws_kms_keyring.py b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/aws_kms_keyring.py
index e846ec695..c05409ca4 100644
--- a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/aws_kms_keyring.py
+++ b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/aws_kms_keyring.py
@@ -4,10 +4,10 @@
 
 import aws_encryption_sdk
 import boto3
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 
 
 def create_keyring(
diff --git a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/hierarchy_keyring.py b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/hierarchy_keyring.py
index b1bdc6913..8ee7b8992 100644
--- a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/hierarchy_keyring.py
+++ b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/hierarchy_keyring.py
@@ -4,17 +4,17 @@
 
 import aws_encryption_sdk
 import boto3
-from aws_cryptographic_materialproviders.keystore import KeyStore
-from aws_cryptographic_materialproviders.keystore.config import KeyStoreConfig
-from aws_cryptographic_materialproviders.keystore.models import KMSConfigurationKmsKeyArn
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.keystore import KeyStore
+from aws_cryptographic_material_providers.keystore.config import KeyStoreConfig
+from aws_cryptographic_material_providers.keystore.models import KMSConfigurationKmsKeyArn
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CacheTypeDefault,
     CreateAwsKmsHierarchicalKeyringInput,
     DefaultCache,
 )
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 
 from ..utils.util import PerfTestUtils
 
diff --git a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_aes_keyring.py b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_aes_keyring.py
index a2a3c9ab1..08be9d216 100644
--- a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_aes_keyring.py
+++ b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_aes_keyring.py
@@ -3,10 +3,10 @@
 """Performance tests for the Raw AES keyring."""
 
 import aws_encryption_sdk
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import AesWrappingAlg, CreateRawAesKeyringInput
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 
 from ..utils.util import PerfTestUtils
 
diff --git a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_rsa_keyring.py b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_rsa_keyring.py
index 6eed281bd..48894330e 100644
--- a/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_rsa_keyring.py
+++ b/performance_tests/src/aws_encryption_sdk_performance_tests/keyrings/raw_rsa_keyring.py
@@ -2,10 +2,10 @@
 # SPDX-License-Identifier: Apache-2.0
 """Performance tests for the Raw RSA keyring."""
 import aws_encryption_sdk
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import CreateRawRsaKeyringInput, PaddingScheme
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 
 
 def create_keyring(public_key, private_key):
diff --git a/requirements_mpl.txt b/requirements_mpl.txt
index 5cbdb37a1..9d72dfb8e 100644
--- a/requirements_mpl.txt
+++ b/requirements_mpl.txt
@@ -1 +1 @@
-aws-cryptographic-materialproviders @ git+https://github.com/aws/aws-cryptographic-material-providers-library.git@python-with-dafny-code#subdirectory=AwsCryptographicMaterialProviders/runtimes/python
+aws-cryptographic-material-providers @ git+https://github.com/aws/aws-cryptographic-material-providers-library.git@python-main-with-dafny-code#subdirectory=AwsCryptographicMaterialProviders/runtimes/python
diff --git a/setup.py b/setup.py
index 3af72f984..6260c1ad2 100644
--- a/setup.py
+++ b/setup.py
@@ -43,9 +43,9 @@ def get_requirements():
     # TODO-MPL: Point at PyPI once MPL is released.
     # This blocks releasing ESDK-Python MPL integration.
     extras_require={
-        "MPL": ["aws-cryptographic-materialproviders @" \
+        "MPL": ["aws-cryptographic-material-providers @" \
                 "git+https://github.com/aws/aws-cryptographic-material-providers-library.git@" \
-                "python-with-dafny-code#subdirectory=AwsCryptographicMaterialProviders/runtimes/python"],
+                "python-main-with-dafny-code#subdirectory=AwsCryptographicMaterialProviders/runtimes/python"],
     },
     classifiers=[
         "Development Status :: 5 - Production/Stable",
diff --git a/src/aws_encryption_sdk/__init__.py b/src/aws_encryption_sdk/__init__.py
index 9f3525349..326dacc13 100644
--- a/src/aws_encryption_sdk/__init__.py
+++ b/src/aws_encryption_sdk/__init__.py
@@ -96,10 +96,10 @@ def encrypt(self, **kwargs):
         .. code:: python
 
             >>> import boto3
-            >>> from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-            >>> from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-            >>> from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-            >>> from aws_cryptographic_materialproviders.mpl.references import IKeyring
+            >>> from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+            >>> from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+            >>> from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+            >>> from aws_cryptographic_material_providers.mpl.references import IKeyring
             >>> import aws_encryption_sdk
             >>> client = aws_encryption_sdk.EncryptionSDKClient()
             >>> mat_prov: AwsCryptographicMaterialProviders = AwsCryptographicMaterialProviders(
@@ -129,7 +129,7 @@ def encrypt(self, **kwargs):
         :type key_provider: aws_encryption_sdk.key_providers.base.MasterKeyProvider
         :param keyring: `IKeyring` that returns keyring for encryption
             (requires either `materials_manager` or `keyring`)
-        :type keyring: aws_cryptographic_materialproviders.mpl.references.IKeyring
+        :type keyring: aws_cryptographic_material_providers.mpl.references.IKeyring
         :param int source_length: Length of source data (optional)
 
             .. note::
@@ -164,10 +164,10 @@ def decrypt(self, **kwargs):
         .. code:: python
 
             >>> import boto3
-            >>> from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-            >>> from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-            >>> from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-            >>> from aws_cryptographic_materialproviders.mpl.references import IKeyring
+            >>> from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+            >>> from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+            >>> from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+            >>> from aws_cryptographic_material_providers.mpl.references import IKeyring
             >>> import aws_encryption_sdk
             >>> client = aws_encryption_sdk.EncryptionSDKClient()
             >>> mat_prov: AwsCryptographicMaterialProviders = AwsCryptographicMaterialProviders(
@@ -197,7 +197,7 @@ def decrypt(self, **kwargs):
         :type key_provider: aws_encryption_sdk.key_providers.base.MasterKeyProvider
         :param keyring: `IKeyring` that returns keyring for encryption
             (requires either `materials_manager` or `keyring`)
-        :type keyring: aws_cryptographic_materialproviders.mpl.references.IKeyring
+        :type keyring: aws_cryptographic_material_providers.mpl.references.IKeyring
         :param int source_length: Length of source data (optional)
 
             .. note::
@@ -238,10 +238,10 @@ def stream(self, **kwargs):
         .. code:: python
 
             >>> import boto3
-            >>> from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-            >>> from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-            >>> from aws_cryptographic_materialproviders.mpl.models import CreateAwsKmsKeyringInput
-            >>> from aws_cryptographic_materialproviders.mpl.references import IKeyring
+            >>> from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+            >>> from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+            >>> from aws_cryptographic_material_providers.mpl.models import CreateAwsKmsKeyringInput
+            >>> from aws_cryptographic_material_providers.mpl.references import IKeyring
             >>> import aws_encryption_sdk
             >>> client = aws_encryption_sdk.EncryptionSDKClient()
             >>> mat_prov: AwsCryptographicMaterialProviders = AwsCryptographicMaterialProviders(
diff --git a/src/aws_encryption_sdk/internal/formatting/serialize.py b/src/aws_encryption_sdk/internal/formatting/serialize.py
index f2920a1ac..c9679a08d 100644
--- a/src/aws_encryption_sdk/internal/formatting/serialize.py
+++ b/src/aws_encryption_sdk/internal/formatting/serialize.py
@@ -196,7 +196,7 @@ def _serialize_header_auth_v1(
     :type signer: aws_encryption_sdk.Signer
     :param required_encryption_context_bytes: Serialized encryption context items
         for all items whose keys are in the required_encryption_context list.
-        This is ONLY processed if using the aws-cryptographic-materialproviders library
+        This is ONLY processed if using the aws-cryptographic-material-providers library
         AND its required encryption context CMM. (optional)
     :type required_encryption_context_bytes: bytes
     :returns: Serialized header authentication data
@@ -250,7 +250,7 @@ def _serialize_header_auth_v2(
     :type signer: aws_encryption_sdk.Signer
     :param required_encryption_context_bytes: Serialized encryption context items
         for all items whose keys are in the required_encryption_context list.
-        This is ONLY processed if using the aws-cryptographic-materialproviders library
+        This is ONLY processed if using the aws-cryptographic-material-providers library
         AND its required encryption context CMM. (optional)
     :type required_encryption_context_bytes: bytes
     :returns: Serialized header authentication data
@@ -306,7 +306,7 @@ def serialize_header_auth(
     :type signer: aws_encryption_sdk.Signer
     :param required_encryption_context_bytes: Serialized encryption context items
         for all items whose keys are in the required_encryption_context list.
-        This is ONLY processed if using the aws-cryptographic-materialproviders library
+        This is ONLY processed if using the aws-cryptographic-material-providers library
         AND its required encryption context CMM. (optional)
     :type required_encryption_context_bytes: bytes
     :returns: Serialized header authentication data
diff --git a/src/aws_encryption_sdk/key_providers/base.py b/src/aws_encryption_sdk/key_providers/base.py
index a855ee596..5fa99cc1c 100644
--- a/src/aws_encryption_sdk/key_providers/base.py
+++ b/src/aws_encryption_sdk/key_providers/base.py
@@ -12,6 +12,7 @@
     ConfigMismatchError,
     DecryptKeyError,
     IncorrectMasterKeyError,
+    InvalidDataKeyError,
     InvalidKeyIdError,
     MasterKeyProviderError,
 )
@@ -256,7 +257,7 @@ def decrypt_data_key(self, encrypted_data_key, algorithm, encryption_context):
                     # //# input encryption context.
 
                     data_key = master_key.decrypt_data_key(encrypted_data_key, algorithm, encryption_context)
-                except (IncorrectMasterKeyError, DecryptKeyError) as error:
+                except (IncorrectMasterKeyError, DecryptKeyError, InvalidDataKeyError) as error:
                     _LOGGER.debug(
                         "%s raised when attempting to decrypt data key with master key %s",
                         repr(error),
@@ -304,8 +305,8 @@ def decrypt_data_key_from_list(self, encrypted_data_keys, algorithm, encryption_
             try:
                 data_key = self.decrypt_data_key(encrypted_data_key, algorithm, encryption_context)
             # MasterKeyProvider.decrypt_data_key throws DecryptKeyError
-            # but MasterKey.decrypt_data_key throws IncorrectMasterKeyError
-            except (DecryptKeyError, IncorrectMasterKeyError):
+            # but MasterKey.decrypt_data_key throws IncorrectMasterKeyError and InvalidDataKeyError
+            except (DecryptKeyError, IncorrectMasterKeyError, InvalidDataKeyError):
                 continue
             else:
                 break
diff --git a/src/aws_encryption_sdk/materials_managers/__init__.py b/src/aws_encryption_sdk/materials_managers/__init__.py
index 706770405..3d03e1f30 100644
--- a/src/aws_encryption_sdk/materials_managers/__init__.py
+++ b/src/aws_encryption_sdk/materials_managers/__init__.py
@@ -80,7 +80,7 @@ class DecryptionMaterialsRequest(object):
     :type encrypted_data_keys: set of `aws_encryption_sdk.structures.EncryptedDataKey`
     :param dict encryption_context: Encryption context to provide to master keys for underlying decrypt requests
     :param dict reproduced_encryption_context: Encryption context to provide on decrypt.
-        This is ONLY processed if using a CMM from the aws-cryptographic-materialproviders library.
+        This is ONLY processed if using a CMM from the aws-cryptographic-material-providers library.
     """
 
     algorithm = attr.ib(validator=attr.validators.instance_of(Algorithm))
diff --git a/src/aws_encryption_sdk/materials_managers/mpl/cmm.py b/src/aws_encryption_sdk/materials_managers/mpl/cmm.py
index 49a743f89..430417c0d 100644
--- a/src/aws_encryption_sdk/materials_managers/mpl/cmm.py
+++ b/src/aws_encryption_sdk/materials_managers/mpl/cmm.py
@@ -7,11 +7,11 @@
 # pylint should pass even if the MPL isn't installed
 # Also thinks these imports aren't used if it can't import them
 # noqa pylint: disable=import-error,unused-import
-from aws_cryptographic_materialproviders.mpl.errors import (
+from aws_cryptographic_material_providers.mpl.errors import (
     AwsCryptographicMaterialProvidersException,
     CollectionOfErrors,
 )
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl.models import (
     AlgorithmSuiteIdESDK as MPL_AlgorithmSuiteIdESDK,
     CommitmentPolicyESDK as MPL_CommitmentPolicyESDK,
     DecryptMaterialsInput as MPL_DecryptMaterialsInput,
@@ -20,7 +20,7 @@
     GetEncryptionMaterialsInput as MPL_GetEncryptionMaterialsInput,
     GetEncryptionMaterialsOutput as MPL_GetEncryptionMaterialsOutput,
 )
-from aws_cryptographic_materialproviders.mpl.references import (
+from aws_cryptographic_material_providers.mpl.references import (
     ICryptographicMaterialsManager as MPL_ICryptographicMaterialsManager,
 )
 # noqa pylint: enable=import-error,unused-import
@@ -38,7 +38,7 @@
 class CryptoMaterialsManagerFromMPL(CryptoMaterialsManager):
     """
     In instances where encryption materials are provided by an implementation of the MPL's
-    `aws_cryptographic_materialproviders.mpl.references.MPL_ICryptographicMaterialsManager`,
+    `aws_cryptographic_material_providers.mpl.references.MPL_ICryptographicMaterialsManager`,
     this maps the ESDK-Python CMM interfaces to the MPL CMM.
     """
 
diff --git a/src/aws_encryption_sdk/materials_managers/mpl/materials.py b/src/aws_encryption_sdk/materials_managers/mpl/materials.py
index 54ea21b39..c2ae305ed 100644
--- a/src/aws_encryption_sdk/materials_managers/mpl/materials.py
+++ b/src/aws_encryption_sdk/materials_managers/mpl/materials.py
@@ -6,7 +6,7 @@
 """
 # pylint should pass even if the MPL isn't installed
 # noqa pylint: disable=import-error
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl.models import (
     DecryptionMaterials as MPL_DecryptionMaterials,
     EncryptedDataKey as MPL_EncryptedDataKey,
     EncryptionMaterials as MPL_EncryptionMaterials,
@@ -30,7 +30,7 @@ def _mpl_algorithm_id_to_native_algorithm_id(mpl_algorithm_id: str) -> int:
 class EncryptionMaterialsFromMPL(Native_EncryptionMaterials):
     """
     In instances where encryption materials are be provided by
-    the MPL's `aws_cryptographic_materialproviders.mpl.models.EncryptionMaterials`,
+    the MPL's `aws_cryptographic_material_providers.mpl.models.EncryptionMaterials`,
     this maps the ESDK interfaces to the underlying MPL materials.
     """
 
@@ -107,7 +107,7 @@ def required_encryption_context_keys(self) -> bytes:
 class DecryptionMaterialsFromMPL(Native_DecryptionMaterials):
     """
     In instances where decryption materials are be provided by
-    the MPL's `aws_cryptographic_materialproviders.mpl.models.DecryptionMaterials`,
+    the MPL's `aws_cryptographic_material_providers.mpl.models.DecryptionMaterials`,
     this maps the ESDK interfaces to the underlying MPL materials.
     """
 
diff --git a/src/aws_encryption_sdk/streaming_client.py b/src/aws_encryption_sdk/streaming_client.py
index 64d77b91a..0eb5670b4 100644
--- a/src/aws_encryption_sdk/streaming_client.py
+++ b/src/aws_encryption_sdk/streaming_client.py
@@ -63,11 +63,11 @@
 try:
     # pylint should pass even if the MPL isn't installed
     # noqa pylint: disable=import-error
-    from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-    from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-    from aws_cryptographic_materialproviders.mpl.errors import AwsCryptographicMaterialProvidersException
-    from aws_cryptographic_materialproviders.mpl.models import CreateDefaultCryptographicMaterialsManagerInput
-    from aws_cryptographic_materialproviders.mpl.references import (
+    from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+    from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+    from aws_cryptographic_material_providers.mpl.errors import AwsCryptographicMaterialProvidersException
+    from aws_cryptographic_material_providers.mpl.models import CreateDefaultCryptographicMaterialsManagerInput
+    from aws_cryptographic_material_providers.mpl.references import (
         ICryptographicMaterialsManager as MPL_ICryptographicMaterialsManager,
         IKeyring as MPL_IKeyring,
     )
@@ -425,10 +425,10 @@ class EncryptorConfig(_ClientConfig):
     :param key_provider: `MasterKeyProvider` from which to obtain data keys for encryption
         (either `materials_manager` or `key_provider` required)
     :type key_provider: aws_encryption_sdk.key_providers.base.MasterKeyProvider
-    :param keyring: `IKeyring` from the aws_cryptographic_materialproviders library
+    :param keyring: `IKeyring` from the aws_cryptographic_material_providers library
         which handles encryption and decryption
     :type keyring:
-        aws_cryptographic_materialproviders.mpl.references.IKeyring
+        aws_cryptographic_material_providers.mpl.references.IKeyring
     :param int source_length: Length of source data (optional)
 
         .. note::
@@ -480,10 +480,10 @@ class StreamEncryptor(_EncryptionStream):  # pylint: disable=too-many-instance-a
     :param key_provider: `MasterKeyProvider` from which to obtain data keys for encryption
         (either `materials_manager` or `key_provider` required)
     :type key_provider: aws_encryption_sdk.key_providers.base.MasterKeyProvider
-    :param keyring: `IKeyring` from the aws_cryptographic_materialproviders library
+    :param keyring: `IKeyring` from the aws_cryptographic_material_providers library
         which handles encryption and decryption
     :type keyring:
-        aws_cryptographic_materialproviders.mpl.references.IKeyring
+        aws_cryptographic_material_providers.mpl.references.IKeyring
     :param int source_length: Length of source data (optional)
 
         .. note::
@@ -867,10 +867,10 @@ class DecryptorConfig(_ClientConfig):
     :param key_provider: `MasterKeyProvider` from which to obtain data keys for decryption
         (either `keyring`, `materials_manager` or `key_provider` required)
     :type key_provider: aws_encryption_sdk.key_providers.base.MasterKeyProvider
-    :param keyring: `IKeyring` from the aws_cryptographic_materialproviders library
+    :param keyring: `IKeyring` from the aws_cryptographic_material_providers library
         which handles encryption and decryption
     :type keyring:
-        aws_cryptographic_materialproviders.mpl.references.IKeyring
+        aws_cryptographic_material_providers.mpl.references.IKeyring
     :param int source_length: Length of source data (optional)
 
         .. note::
@@ -915,10 +915,10 @@ class StreamDecryptor(_EncryptionStream):  # pylint: disable=too-many-instance-a
     :param key_provider: `MasterKeyProvider` from which to obtain data keys for decryption
         (either `materials_manager` or `key_provider` required)
     :type key_provider: aws_encryption_sdk.key_providers.base.MasterKeyProvider
-    :param keyring: `IKeyring` from the aws_cryptographic_materialproviders library
+    :param keyring: `IKeyring` from the aws_cryptographic_material_providers library
         which handles encryption and decryption
     :type keyring:
-        aws_cryptographic_materialproviders.mpl.references.IKeyring
+        aws_cryptographic_material_providers.mpl.references.IKeyring
     :param int source_length: Length of source data (optional)
 
         .. note::
diff --git a/test/mpl/integ/test_required_ec_cmm.py b/test/mpl/integ/test_required_ec_cmm.py
index c99528f70..ab308ed54 100644
--- a/test/mpl/integ/test_required_ec_cmm.py
+++ b/test/mpl/integ/test_required_ec_cmm.py
@@ -3,9 +3,9 @@
 import copy
 
 import pytest
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateDefaultCryptographicMaterialsManagerInput,
     CreateRequiredEncryptionContextCMMInput,
 )
diff --git a/test/mpl/unit/test_material_managers_mpl_cmm.py b/test/mpl/unit/test_material_managers_mpl_cmm.py
index 603446550..e8d6ceb8b 100644
--- a/test/mpl/unit/test_material_managers_mpl_cmm.py
+++ b/test/mpl/unit/test_material_managers_mpl_cmm.py
@@ -6,8 +6,8 @@
 """
 
 import pytest
-from aws_cryptographic_materialproviders.mpl.errors import AwsCryptographicMaterialProvidersException
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl.errors import AwsCryptographicMaterialProvidersException
+from aws_cryptographic_material_providers.mpl.models import (
     AlgorithmSuiteIdESDK as MPL_AlgorithmSuiteIdESDK,
     CommitmentPolicyESDK as MPL_CommitmentPolicyESDK,
     DecryptionMaterials as MPL_DecryptionMaterials,
@@ -16,7 +16,7 @@
     GetEncryptionMaterialsInput as MPL_GetEncryptionMaterialsInput,
     GetEncryptionMaterialsOutput as MPL_GetEncryptionMaterialsOutput,
 )
-from aws_cryptographic_materialproviders.mpl.references import (
+from aws_cryptographic_material_providers.mpl.references import (
     ICryptographicMaterialsManager as MPL_ICryptographicMaterialsManager,
 )
 from mock import MagicMock, patch
diff --git a/test/mpl/unit/test_material_managers_mpl_materials.py b/test/mpl/unit/test_material_managers_mpl_materials.py
index 8d9052c0a..0466a6424 100644
--- a/test/mpl/unit/test_material_managers_mpl_materials.py
+++ b/test/mpl/unit/test_material_managers_mpl_materials.py
@@ -6,7 +6,7 @@
 """
 
 import pytest
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl.models import (
     DecryptionMaterials as MPL_DecryptionMaterials,
     EncryptedDataKey as MPL_EncryptedDataKey,
     EncryptionMaterials as MPL_EncryptionMaterials,
diff --git a/test/mpl/utils.py b/test/mpl/utils.py
index 0809aace4..a3168c02c 100644
--- a/test/mpl/utils.py
+++ b/test/mpl/utils.py
@@ -5,12 +5,12 @@
 import string
 
 import boto3
-from aws_cryptographic_materialproviders.keystore import KeyStore
-from aws_cryptographic_materialproviders.keystore.config import KeyStoreConfig
-from aws_cryptographic_materialproviders.keystore.models import KMSConfigurationKmsKeyArn
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.keystore import KeyStore
+from aws_cryptographic_material_providers.keystore.config import KeyStoreConfig
+from aws_cryptographic_material_providers.keystore.models import KMSConfigurationKmsKeyArn
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     AesWrappingAlg,
     CacheTypeDefault,
     CreateAwsKmsHierarchicalKeyringInput,
@@ -21,7 +21,7 @@
     DefaultCache,
     PaddingScheme,
 )
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.references import IKeyring
 from cryptography.hazmat.backends import default_backend as crypto_default_backend
 from cryptography.hazmat.primitives import serialization as crypto_serialization
 from cryptography.hazmat.primitives.asymmetric import rsa
diff --git a/test/unit/test_streaming_client_configs.py b/test/unit/test_streaming_client_configs.py
index fc066ef1a..d0ecefcf4 100644
--- a/test/unit/test_streaming_client_configs.py
+++ b/test/unit/test_streaming_client_configs.py
@@ -23,7 +23,7 @@
 # Ideally, this logic would be based on mocking imports and testing logic,
 # but doing that introduces errors that cause other tests to fail.
 try:
-    from aws_cryptographic_materialproviders.mpl.references import ICryptographicMaterialsManager, IKeyring
+    from aws_cryptographic_material_providers.mpl.references import ICryptographicMaterialsManager, IKeyring
     HAS_MPL = True
 
     from aws_encryption_sdk.materials_managers.mpl.cmm import CryptoMaterialsManagerFromMPL
diff --git a/test/unit/test_streaming_client_mpl_import.py b/test/unit/test_streaming_client_mpl_import.py
index 638b04fd6..0dcd8a981 100644
--- a/test/unit/test_streaming_client_mpl_import.py
+++ b/test/unit/test_streaming_client_mpl_import.py
@@ -13,7 +13,7 @@
 # Ideally, this logic would be based on mocking imports and testing logic,
 # but doing that introduces errors that cause other tests to fail.
 try:
-    import aws_cryptographic_materialproviders  # noqa pylint: disable=unused-import
+    import aws_cryptographic_material_providers  # noqa pylint: disable=unused-import
     HAS_MPL = True
 except ImportError:
     HAS_MPL = False
diff --git a/test_vector_handlers/requirements_mpl.txt b/test_vector_handlers/requirements_mpl.txt
index 6cffc62e6..6995b3187 100644
--- a/test_vector_handlers/requirements_mpl.txt
+++ b/test_vector_handlers/requirements_mpl.txt
@@ -1 +1 @@
-aws-cryptography-internal-mpl-testvectors @ git+https://github.com/aws/aws-cryptographic-material-providers-library.git@python-with-dafny-code#subdirectory=TestVectorsAwsCryptographicMaterialProviders/runtimes/python
\ No newline at end of file
+aws-cryptography-internal-mpl-testvectors @ git+https://github.com/aws/aws-cryptographic-material-providers-library.git@python-main-with-dafny-code#subdirectory=TestVectorsAwsCryptographicMaterialProviders/runtimes/python
\ No newline at end of file
diff --git a/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt.py b/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt.py
index d1e7a6811..91b68287a 100644
--- a/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt.py
+++ b/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt.py
@@ -6,7 +6,7 @@
 from awses_test_vectors.manifests.full_message.decrypt import MessageDecryptionManifest
 
 try:
-    import aws_cryptographic_materialproviders  # noqa pylint: disable=unused-import,import-error
+    import aws_cryptographic_material_providers  # noqa pylint: disable=unused-import,import-error
     _HAS_MPL = True
 except ImportError:
     _HAS_MPL = False
diff --git a/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt_generate.py b/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt_generate.py
index 49f2647fa..6383f7229 100644
--- a/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt_generate.py
+++ b/test_vector_handlers/src/awses_test_vectors/commands/full_message_decrypt_generate.py
@@ -6,7 +6,7 @@
 from awses_test_vectors.manifests.full_message.decrypt_generation import MessageDecryptionGenerationManifest
 
 try:
-    import aws_cryptographic_materialproviders  # noqa pylint: disable=unused-import,import-error
+    import aws_cryptographic_material_providers  # noqa pylint: disable=unused-import,import-error
     _HAS_MPL = True
 except ImportError:
     _HAS_MPL = False
diff --git a/test_vector_handlers/src/awses_test_vectors/commands/full_message_encrypt.py b/test_vector_handlers/src/awses_test_vectors/commands/full_message_encrypt.py
index ba7579e6f..1025b9426 100644
--- a/test_vector_handlers/src/awses_test_vectors/commands/full_message_encrypt.py
+++ b/test_vector_handlers/src/awses_test_vectors/commands/full_message_encrypt.py
@@ -6,7 +6,7 @@
 from awses_test_vectors.manifests.full_message.encrypt import MessageEncryptionManifest
 
 try:
-    import aws_cryptographic_materialproviders  # noqa pylint: disable=unused-import,import-error
+    import aws_cryptographic_material_providers  # noqa pylint: disable=unused-import,import-error
     _HAS_MPL = True
 except ImportError:
     _HAS_MPL = False
diff --git a/test_vector_handlers/src/awses_test_vectors/internal/mpl/tampering_mpl_materials.py b/test_vector_handlers/src/awses_test_vectors/internal/mpl/tampering_mpl_materials.py
index 29a820ecc..00a0eb252 100644
--- a/test_vector_handlers/src/awses_test_vectors/internal/mpl/tampering_mpl_materials.py
+++ b/test_vector_handlers/src/awses_test_vectors/internal/mpl/tampering_mpl_materials.py
@@ -16,9 +16,9 @@
 from aws_encryption_sdk.materials_managers.mpl.cmm import (
     CryptoMaterialsManagerFromMPL
 )
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.models import (
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.models import (
     CreateDefaultCryptographicMaterialsManagerInput,
 )
 
diff --git a/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt.py b/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt.py
index 79df4f2cf..0f5b2e680 100644
--- a/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt.py
+++ b/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt.py
@@ -29,10 +29,10 @@
 
 try:
     from awses_test_vectors.manifests.mpl_keyring import KeyringSpec, keyring_from_master_key_specs
-    from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-    from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-    from aws_cryptographic_materialproviders.mpl.references import ICryptographicMaterialsManager
-    from aws_cryptographic_materialproviders.mpl.models import (
+    from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+    from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+    from aws_cryptographic_material_providers.mpl.references import ICryptographicMaterialsManager
+    from aws_cryptographic_material_providers.mpl.models import (
         CreateDefaultCryptographicMaterialsManagerInput,
         CreateRequiredEncryptionContextCMMInput,
     )
diff --git a/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt_generation.py b/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt_generation.py
index 63f8b8ff3..2e94dc6a7 100644
--- a/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt_generation.py
+++ b/test_vector_handlers/src/awses_test_vectors/manifests/full_message/decrypt_generation.py
@@ -19,12 +19,12 @@
 from aws_encryption_sdk.materials_managers.default import DefaultCryptoMaterialsManager
 
 try:
-    from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-    from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-    from aws_cryptographic_materialproviders.mpl.references import (
+    from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+    from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+    from aws_cryptographic_material_providers.mpl.references import (
         IKeyring,
     )
-    from aws_cryptographic_materialproviders.mpl.models import (
+    from aws_cryptographic_material_providers.mpl.models import (
         CreateDefaultCryptographicMaterialsManagerInput,
     )
     from aws_encryption_sdk.materials_managers.mpl.cmm import CryptoMaterialsManagerFromMPL
diff --git a/test_vector_handlers/src/awses_test_vectors/manifests/full_message/encrypt.py b/test_vector_handlers/src/awses_test_vectors/manifests/full_message/encrypt.py
index 81581fa8e..2a6795902 100644
--- a/test_vector_handlers/src/awses_test_vectors/manifests/full_message/encrypt.py
+++ b/test_vector_handlers/src/awses_test_vectors/manifests/full_message/encrypt.py
@@ -33,7 +33,7 @@
     from aws_encryption_sdk.identifiers import Algorithm as AlgorithmSuite
 
 try:
-    from aws_cryptographic_materialproviders.mpl.references import (
+    from aws_cryptographic_material_providers.mpl.references import (
         IKeyring,
     )
 
diff --git a/test_vector_handlers/src/awses_test_vectors/manifests/master_key.py b/test_vector_handlers/src/awses_test_vectors/manifests/master_key.py
index 7e64f9983..96af030d7 100644
--- a/test_vector_handlers/src/awses_test_vectors/manifests/master_key.py
+++ b/test_vector_handlers/src/awses_test_vectors/manifests/master_key.py
@@ -7,8 +7,9 @@
 """
 import attr
 import six
+from aws_encryption_sdk.exceptions import InvalidKeyIdError
 from aws_encryption_sdk.identifiers import EncryptionKeyType, WrappingAlgorithm
-from aws_encryption_sdk.key_providers.base import MasterKeyProvider  # noqa pylint: disable=unused-import
+from aws_encryption_sdk.key_providers.base import MasterKeyProvider, MasterKeyProviderConfig
 from aws_encryption_sdk.key_providers.kms import (  # noqa pylint: disable=unused-import
     DiscoveryFilter,
     KMSMasterKey,
@@ -290,6 +291,44 @@ def scenario_spec(self):
         return spec
 
 
+class TestVectorsMultiMasterKeyProvider(MasterKeyProvider):
+    """
+    Provider for other MasterKeyProviders.
+    Acts as a "multi" MasterKeyProvider for use in test vectors.
+
+    There is some disagreement between the spec
+    and how Python ESDK implements MasterKey;
+    this class fills that gap.
+
+    In the ESDK-Python, MasterKey extends MasterKeyProvider;
+    i.e. MasterKey "is a" MasterKeyProvider; isinstance(some_master_key, MasterKeyProvider) == True.
+
+    From AWS ESDK specification:
+    "A master key MUST supply itself and MUST NOT supply any other master keys."
+    https://github.com/awslabs/aws-encryption-sdk-specification/blob/master/framework/master-key-interface.md#get-master-key
+
+    The MasterKey class overrides MasterKeyProvider's `decrypt_data_key` method to correct this gap.
+    However, this modification suggests that this "is a" relationship is not entirely true.
+
+    master_key_provider_from_master_key_specs expects to return a MasterKeyProvider, not a MasterKey.
+    master_key_provider_from_master_key_specs uses this class to always return a MasterKeyProvider
+    that wraps any MasterKeyProvider or MasterKey loaded from a spec.
+    """
+
+    _config_class = MasterKeyProviderConfig
+    provider_id = "aws-test-vectors-multi-master-key-provider"
+    _members = []
+
+    def add_key(self, key_provider):
+        """Add a MKP to the list of configured MKPs."""
+        self._members.append(key_provider)
+
+    def _new_master_key(self, key_id):
+        # This MKP does not have a key associated with it.
+        # ESDK-Python will find keys in _members.
+        raise InvalidKeyIdError()
+
+
 def master_key_provider_from_master_key_specs(keys, master_key_specs):
     # type: (KeysManifest, Iterable[MasterKeySpec]) -> MasterKeyProvider
     """Build and combine all master key providers identified by the provided specs and
@@ -312,8 +351,7 @@ def master_key_provider_from_master_key_specs(keys, master_key_specs):
             pass
     if len(master_keys) == 0:
         return None
-    primary = master_keys[0]
-    others = master_keys[1:]
-    for master_key in others:
-        primary.add_master_key_provider(master_key)
-    return primary
+    mkp = TestVectorsMultiMasterKeyProvider()
+    for master_key in master_keys:
+        mkp.add_key(master_key)
+    return mkp
diff --git a/test_vector_handlers/src/awses_test_vectors/manifests/mpl_keyring.py b/test_vector_handlers/src/awses_test_vectors/manifests/mpl_keyring.py
index f2ea05559..8d972d2c5 100644
--- a/test_vector_handlers/src/awses_test_vectors/manifests/mpl_keyring.py
+++ b/test_vector_handlers/src/awses_test_vectors/manifests/mpl_keyring.py
@@ -25,10 +25,10 @@
         GetKeyDescriptionOutput,
         TestVectorKeyringInput,
     )
-from aws_cryptographic_materialproviders.mpl import AwsCryptographicMaterialProviders
-from aws_cryptographic_materialproviders.mpl.config import MaterialProvidersConfig
-from aws_cryptographic_materialproviders.mpl.references import IKeyring
-from aws_cryptographic_materialproviders.mpl.models import CreateMultiKeyringInput
+from aws_cryptographic_material_providers.mpl import AwsCryptographicMaterialProviders
+from aws_cryptographic_material_providers.mpl.config import MaterialProvidersConfig
+from aws_cryptographic_material_providers.mpl.references import IKeyring
+from aws_cryptographic_material_providers.mpl.models import CreateMultiKeyringInput
 
 import _dafny
 from smithy_dafny_standard_library.internaldafny.generated import UTF8