diff --git a/internal/provider/group_resource.go b/internal/provider/group_resource.go
index c7f11bd..eeb6ebe 100644
--- a/internal/provider/group_resource.go
+++ b/internal/provider/group_resource.go
@@ -77,13 +77,18 @@ func (r *GroupResource) Schema(ctx context.Context, req resource.SchemaRequest,
 			"name": schema.StringAttribute{
 				MarkdownDescription: "The unique name of the group.",
 				Required:            true,
+				Validators: []validator.String{
+					stringvalidator.LengthBetween(1, 36),
+					stringvalidator.RegexMatches(nameValidRegex, "Group names must be alpahnumeric with hyphens."),
+				},
 			},
 			"display_name": schema.StringAttribute{
 				MarkdownDescription: "The display name of the group. Defaults to the group name.",
 				Computed:            true,
 				Optional:            true,
 				Validators: []validator.String{
-					stringvalidator.LengthAtLeast(1),
+					stringvalidator.LengthBetween(1, 64),
+					stringvalidator.RegexMatches(displayNameRegex, "Group display names must be alphanumeric with spaces"),
 				},
 				Default: stringdefault.StaticString(""),
 			},
diff --git a/internal/provider/template_resource.go b/internal/provider/template_resource.go
index 9255f2f..2292491 100644
--- a/internal/provider/template_resource.go
+++ b/internal/provider/template_resource.go
@@ -248,12 +248,17 @@ func (r *TemplateResource) Schema(ctx context.Context, req resource.SchemaReques
 				Required:            true,
 				Validators: []validator.String{
 					stringvalidator.LengthBetween(1, 32),
+					stringvalidator.RegexMatches(nameValidRegex, "Template names must be alphanumeric with hyphens."),
 				},
 			},
 			"display_name": schema.StringAttribute{
 				MarkdownDescription: "The display name of the template. Defaults to the template name.",
 				Optional:            true,
 				Computed:            true,
+				Validators: []validator.String{
+					stringvalidator.LengthBetween(1, 64),
+					stringvalidator.RegexMatches(displayNameRegex, "Template display names must be alphanumeric with spaces."),
+				},
 			},
 			"description": schema.StringAttribute{
 				MarkdownDescription: "A description of the template.",
@@ -394,7 +399,8 @@ func (r *TemplateResource) Schema(ctx context.Context, req resource.SchemaReques
 							Optional:            true,
 							Computed:            true,
 							Validators: []validator.String{
-								stringvalidator.LengthAtLeast(1),
+								stringvalidator.LengthBetween(1, 64),
+								stringvalidator.RegexMatches(templateVersionNameRegex, "Template version names must be alphanumeric with underscores and dots."),
 							},
 						},
 						"message": schema.StringAttribute{
diff --git a/internal/provider/user_resource.go b/internal/provider/user_resource.go
index 4e8de49..6bec177 100644
--- a/internal/provider/user_resource.go
+++ b/internal/provider/user_resource.go
@@ -71,11 +71,18 @@ func (r *UserResource) Schema(ctx context.Context, req resource.SchemaRequest, r
 			"username": schema.StringAttribute{
 				MarkdownDescription: "Username of the user.",
 				Required:            true,
+				Validators: []validator.String{
+					stringvalidator.LengthBetween(1, 32),
+					stringvalidator.RegexMatches(nameValidRegex, "Username must be alphanumeric with hyphens."),
+				},
 			},
 			"name": schema.StringAttribute{
 				MarkdownDescription: "Display name of the user. Defaults to username.",
 				Computed:            true,
 				Optional:            true,
+				Validators: []validator.String{
+					stringvalidator.LengthBetween(1, 128),
+				},
 			},
 			"email": schema.StringAttribute{
 				MarkdownDescription: "Email address of the user.",
diff --git a/internal/provider/util.go b/internal/provider/util.go
index 03d899f..cdcee5b 100644
--- a/internal/provider/util.go
+++ b/internal/provider/util.go
@@ -6,10 +6,17 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"regexp"
 
 	"github.com/google/uuid"
 )
 
+var (
+	nameValidRegex           = regexp.MustCompile("^[a-zA-Z0-9]+(?:-[a-zA-Z0-9]+)*$")
+	templateVersionNameRegex = regexp.MustCompile(`^[a-zA-Z0-9]+(?:[_.-]{1}[a-zA-Z0-9]+)*$`)
+	displayNameRegex         = regexp.MustCompile(`^[^\s](.*[^\s])?$`)
+)
+
 func PtrTo[T any](v T) *T {
 	return &v
 }