diff --git a/doc/api.rst b/doc/api.rst
index 031e3d9f1bf..8cf77d104f0 100644
--- a/doc/api.rst
+++ b/doc/api.rst
@@ -18,7 +18,6 @@ Internals
 CLI
 ---
 
-.. automethod:: tmuxp.cli._reattach
 .. automethod:: tmuxp.cli.get_config_dir
 .. automethod:: tmuxp.cli.get_teamocil_dir
 .. automethod:: tmuxp.cli.get_tmuxinator_dir
diff --git a/doc/cli.rst b/doc/cli.rst
index 9fc5ba7b07c..40b10438ef2 100644
--- a/doc/cli.rst
+++ b/doc/cli.rst
@@ -84,6 +84,24 @@ without being attached. The last one will be attached if there is no
 
     $ tmuxp load <filename1> <filename2> ...
 
+If you try to load a config file within a tmux session, it will ask you
+if you want to load and attach in the new session or just load detached.
+You can also load config appending windows in the current active session.
+
+::
+
+    Already inside TMUX, switch to session? yes/no
+    Or (a)ppend windows in the current active session?
+    [y/n/a]:
+
+All this modes you can force doing:
+
+.. code-block:: bash
+
+    $ tmuxp load -y config # load attached
+    $ tmuxp load -d config # load detached
+    $ tmuxp load -a config # load appending
+
 .. _cli_import:
 
 Import
diff --git a/doc/quickstart.rst b/doc/quickstart.rst
index 380c8edae1c..c89b13871f1 100644
--- a/doc/quickstart.rst
+++ b/doc/quickstart.rst
@@ -55,7 +55,8 @@ Load multiple tmux sessions at once:
     $ tmuxp load example.yaml anothersession.yaml
 
 tmuxp will offer to ``switch-client`` for you if you're already in a
-session.
+session. You can also load config appending windows in the current
+active session.
 
 You can also have a custom tmuxp config directory by setting the
 ``TMUX_CONFIGDIR`` in your environment variables.
diff --git a/tests/fixtures/workspacebuilder/three_windows.yaml b/tests/fixtures/workspacebuilder/three_windows.yaml
new file mode 100644
index 00000000000..6d571088aa5
--- /dev/null
+++ b/tests/fixtures/workspacebuilder/three_windows.yaml
@@ -0,0 +1,15 @@
+session_name: sample_three_windows
+windows:
+- window_name: first
+  panes:
+    - shell_command:
+      - echo 'first window'
+- window_name: second
+  panes:
+    - shell_command:
+      - echo 'second window'
+- window_name: third
+  panes:
+    - shell_command:
+      - echo 'third window'
+
diff --git a/tests/fixtures/workspacebuilder/two_windows.yaml b/tests/fixtures/workspacebuilder/two_windows.yaml
new file mode 100644
index 00000000000..0f1d40f34a9
--- /dev/null
+++ b/tests/fixtures/workspacebuilder/two_windows.yaml
@@ -0,0 +1,10 @@
+session_name: sample_two_windows
+windows:
+- window_name: first
+  panes:
+    - shell_command:
+      - echo 'first window'
+- window_name: second
+  panes:
+    - shell_command:
+      - echo 'second window'
diff --git a/tests/test_workspacebuilder.py b/tests/test_workspacebuilder.py
index 6085ea46d47..93729eedd17 100644
--- a/tests/test_workspacebuilder.py
+++ b/tests/test_workspacebuilder.py
@@ -673,3 +673,51 @@ def test_before_load_true_if_test_passes_with_args(server):
 
     with temp_session(server) as session:
         builder.build(session=session)
+
+
+def test_load_configs_same_session(server):
+    yaml_config = loadfixture("workspacebuilder/three_windows.yaml")
+    sconfig = kaptan.Kaptan(handler='yaml')
+    sconfig = sconfig.import_config(yaml_config).get()
+
+    builder = WorkspaceBuilder(sconf=sconfig, server=server)
+    builder.build()
+
+    assert len(server.sessions) == 1
+    assert len(server.sessions[0]._windows) == 3
+
+    yaml_config = loadfixture("workspacebuilder/two_windows.yaml")
+
+    sconfig = kaptan.Kaptan(handler='yaml')
+    sconfig = sconfig.import_config(yaml_config).get()
+
+    builder = WorkspaceBuilder(sconf=sconfig, server=server)
+    builder.build(server.sessions[0], True)
+
+    assert len(server.sessions) == 1
+    assert len(server.sessions[0]._windows) == 5
+
+
+def test_load_configs_separate_sessions(server):
+    yaml_config = loadfixture("workspacebuilder/three_windows.yaml")
+    sconfig = kaptan.Kaptan(handler='yaml')
+    sconfig = sconfig.import_config(yaml_config).get()
+
+    builder = WorkspaceBuilder(sconf=sconfig, server=server)
+    builder.build()
+
+    assert len(server.sessions) == 1
+    assert len(server.sessions[0]._windows) == 3
+
+    yaml_config = loadfixture("workspacebuilder/two_windows.yaml")
+
+    sconfig = kaptan.Kaptan(handler='yaml')
+    sconfig = sconfig.import_config(yaml_config).get()
+
+    builder = WorkspaceBuilder(sconf=sconfig, server=server)
+    builder.build()
+
+    assert len(server.sessions) == 2
+    assert len(server.sessions[0]._windows) == 3
+    assert len(server.sessions[1]._windows) == 2
+
diff --git a/tmuxp/__about__.py b/tmuxp/__about__.py
index 37322d441f1..859816bd088 100644
--- a/tmuxp/__about__.py
+++ b/tmuxp/__about__.py
@@ -1,6 +1,6 @@
 __title__ = 'tmuxp'
 __package_name__ = 'tmuxp'
-__version__ = '1.5.3'
+__version__ = '1.6.0'
 __description__ = 'tmux session manager'
 __email__ = 'tony@git-pull.com'
 __author__ = 'Tony Narlock'
diff --git a/tmuxp/cli.py b/tmuxp/cli.py
index f74b187c383..fe4bb3bf178 100644
--- a/tmuxp/cli.py
+++ b/tmuxp/cli.py
@@ -368,29 +368,6 @@ def scan_config(config, config_dir=None):
     return config
 
 
-def _reattach(session):
-    """
-    Reattach session (depending on env being inside tmux already or not)
-
-    Parameters
-    ----------
-    session : :class:`libtmux.Session`
-
-    Notes
-    -----
-    If ``TMUX`` environmental variable exists in the environment this script is
-    running, that means we're in a tmux client. So ``tmux switch-client`` will
-    load the session.
-
-    If not, ``tmux attach-session`` loads the client to the target session.
-    """
-    if 'TMUX' in os.environ:
-        session.switch_client()
-
-    else:
-        session.attach_session()
-
-
 def load_workspace(
     config_file,
     socket_name=None,
@@ -398,6 +375,7 @@ def load_workspace(
     colors=None,
     detached=False,
     answer_yes=False,
+    append=False,
 ):
     """
     Load a tmux "workspace" session via tmuxp file.
@@ -416,7 +394,10 @@ def load_workspace(
     detached : bool
         Force detached state. default False.
     answer_yes : bool
-        Assume yes when given prompt. default False.
+        Assume yes when given prompt to attach in a new sesion. default False.
+    append: bool
+        Assume current when given prompt to append windows in in same Session.
+        Default False.
 
     Notes
     -----
@@ -509,60 +490,41 @@ def load_workspace(
         click.echo('%s is empty or parsed no config data' % config_file, err=True)
         return
 
-    session_name = sconfig['session_name']
-
-    # if the session already exists, prompt the user to attach. tmuxp doesn't
-    # support incremental session building or appending (yet, PR's welcome!)
-    if builder.session_exists(session_name):
-        if not detached and (
-            answer_yes
-            or click.confirm(
-                '%s is already running. Attach?'
-                % click.style(session_name, fg='green'),
-                default=True,
-            )
-        ):
-            _reattach(builder.session)
-        return
-
     try:
         click.echo(
             click.style('[Loading] ', fg='green')
             + click.style(config_file, fg='blue', bold=True)
         )
 
-        builder.build()  # load tmux session via workspace builder
+        if detached:
+            load_detached(builder)
+            return builder.session
+
+        if append:
+            if 'TMUX' in os.environ:
+                load_append_windows_same_session(builder)
+            else:
+                load_attached(builder, detached)
+            return builder.session
+
+        if answer_yes:
+            load_attached(builder, detached)
+            return builder.session
 
         if 'TMUX' in os.environ:  # tmuxp ran from inside tmux
-            if not detached and (
-                answer_yes or click.confirm('Already inside TMUX, switch to session?')
-            ):
-                # unset TMUX, save it, e.g. '/tmp/tmux-1000/default,30668,0'
-                tmux_env = os.environ.pop('TMUX')
-
-                if has_gte_version('2.6'):
-                    set_layout_hook(builder.session, 'client-session-changed')
-
-                builder.session.switch_client()  # switch client to new session
-
-                os.environ['TMUX'] = tmux_env  # set TMUX back again
-                return builder.session
-            else:  # session created in the background, from within tmux
-                if has_gte_version('2.6'):  # prepare for both cases
-                    set_layout_hook(builder.session, 'client-attached')
-                    set_layout_hook(builder.session, 'client-session-changed')
-
-                sys.exit('Session created in detached state.')
-        else:  # tmuxp ran from inside tmux
-            if has_gte_version('2.6'):
-                # if attaching for first time
-                set_layout_hook(builder.session, 'client-attached')
-
-                # for cases where user switches client for first time
-                set_layout_hook(builder.session, 'client-session-changed')
-
-            if not detached:
-                builder.session.attach_session()
+            msg = "Already inside TMUX, switch to session? yes/no\n"\
+            "Or (a)ppend windows in the current active session?\n[y/n/a]"
+            options = ['y', 'n', 'a']
+            choice = click.prompt(msg, value_proc=_validate_choices(options))
+
+            if choice == 'y':
+                load_attached(builder, detached)
+            elif choice == 'a':
+                load_append_windows_same_session(builder)
+            else:
+                return load_detached(builder)
+        else:
+            load_attached(builder, detached)
 
     except exc.TmuxpException as e:
         import traceback
@@ -590,6 +552,47 @@ def load_workspace(
     return builder.session
 
 
+def load_attached(builder, detached):
+    """
+        Load config in a new session and attach.
+    """
+    builder.build() # load config in a new session
+    if 'TMUX' in os.environ:
+        # unset TMUX, save it, e.g. '/tmp/tmux-1000/default,30668,0'
+        tmux_env = os.environ.pop('TMUX')
+        if has_gte_version('2.6'):
+            set_layout_hook(builder.session, 'client-session-changed')
+        builder.session.switch_client()  # switch client to new session
+        os.environ['TMUX'] = tmux_env  # set TMUX back again
+    else:
+        if has_gte_version('2.6'):
+            # if attaching for first time
+            set_layout_hook(builder.session, 'client-attached')
+            # for cases where user switches client for first time
+            set_layout_hook(builder.session, 'client-session-changed')
+        if not detached:
+            builder.session.attach_session()
+
+
+def load_detached(builder):
+    builder.build()
+    if has_gte_version('2.6'):  # prepare for both cases
+        set_layout_hook(builder.session, 'client-attached')
+        set_layout_hook(builder.session, 'client-session-changed')
+    print('Session created in detached state.')
+
+
+def load_append_windows_same_session(builder):
+    """
+        Load configs in the active session appending windows
+    """
+    current_attached_sesssion = builder.find_current_attached_session()
+    builder.build(current_attached_sesssion, True)
+    if has_gte_version('2.6'):  # prepare for both cases
+        set_layout_hook(builder.session, 'client-attached')
+        set_layout_hook(builder.session, 'client-session-changed')
+
+
 @click.group(context_settings={'obj': {}})
 @click.version_option(__version__, '-V', '--version', message='%(prog)s %(version)s')
 @click.option(
@@ -746,6 +749,9 @@ def command_freeze(session_name, socket_name, socket_path):
 @click.option(
     '-d', 'detached', help='Load the session without attaching it', is_flag=True
 )
+@click.option(
+    '-a', 'append', help='Load appending windows in active session', is_flag=True
+)
 @click.option(
     'colors',
     '-2',
@@ -759,7 +765,16 @@ def command_freeze(session_name, socket_name, socket_path):
     flag_value=88,
     help='Like -2, but indicates that the terminal supports 88 colours.',
 )
-def command_load(ctx, config, socket_name, socket_path, answer_yes, detached, colors):
+def command_load(
+    ctx,
+    config,
+    socket_name,
+    socket_path,
+    answer_yes,
+    detached,
+    colors,
+    append
+):
     """Load a tmux workspace from each CONFIG.
 
     CONFIG is a specifier for a configuration file.
@@ -790,6 +805,7 @@ def command_load(ctx, config, socket_name, socket_path, answer_yes, detached, co
         'answer_yes': answer_yes,
         'colors': colors,
         'detached': detached,
+        'append': append
     }
 
     if not config:
diff --git a/tmuxp/workspacebuilder.py b/tmuxp/workspacebuilder.py
index 2cb36492609..4e3cd3888c5 100644
--- a/tmuxp/workspacebuilder.py
+++ b/tmuxp/workspacebuilder.py
@@ -98,15 +98,7 @@ def __init__(self, sconf, server=None):
 
         self.sconf = sconf
 
-    def session_exists(self, session_name=None):
-        exists = self.server.has_session(session_name)
-        if not exists:
-            return exists
-
-        self.session = self.server.find_where({'session_name': session_name})
-        return True
-
-    def build(self, session=None):
+    def build(self, session=None, append=False):
         """
         Build tmux workspace in session.
 
@@ -120,6 +112,8 @@ def build(self, session=None):
         ----------
         session : :class:`libtmux.Session`
             session to build workspace in
+        append : bool
+            append windows in current active session
         """
 
         if not session:
@@ -177,7 +171,7 @@ def build(self, session=None):
             for option, value in self.sconf['environment'].items():
                 self.session.set_environment(option, value)
 
-        for w, wconf in self.iter_create_windows(session):
+        for w, wconf in self.iter_create_windows(session, append):
             assert isinstance(w, Window)
 
             focus_pane = None
@@ -202,7 +196,7 @@ def build(self, session=None):
         if focus:
             focus.select_window()
 
-    def iter_create_windows(self, s):
+    def iter_create_windows(self, session, append_same_sassion=False):
         """
         Return :class:`libtmux.Window` iterating through session config dict.
 
@@ -215,6 +209,9 @@ def iter_create_windows(self, s):
         ----------
         session : :class:`libtmux.Session`
             session to create windows in
+        append_same_sassion : bool
+            trick to identify previous open session and create
+            windows appending in the current session. default False.
 
         Returns
         -------
@@ -228,11 +225,14 @@ def iter_create_windows(self, s):
             else:
                 window_name = wconf['window_name']
 
+            is_first_window_pass = self.first_window_pass(
+                i, session, append_same_sassion
+            )
+
             w1 = None
-            if i == int(1):  # if first window, use window 1
-                w1 = s.attached_window
+            if is_first_window_pass: # if first window, use window 1
+                w1 = session.attached_window
                 w1.move_window(99)
-                pass
 
             if 'start_directory' in wconf:
                 sd = wconf['start_directory']
@@ -244,7 +244,7 @@ def iter_create_windows(self, s):
             else:
                 ws = None
 
-            w = s.new_window(
+            w = session.new_window(
                 window_name=window_name,
                 start_directory=sd,
                 attach=False,  # do not move to the new window
@@ -252,10 +252,13 @@ def iter_create_windows(self, s):
                 window_shell=ws,
             )
 
-            if i == int(1) and w1:  # if first window, use window 1
-                w1.kill_window()
+            if is_first_window_pass:
+                session.attached_window.kill_window()
+
             assert isinstance(w, Window)
-            s.server._update_windows()
+
+            session.server._update_windows()
+
             if 'options' in wconf and isinstance(wconf['options'], dict):
                 for key, val in wconf['options'].items():
                     w.set_window_option(key, val)
@@ -263,7 +266,7 @@ def iter_create_windows(self, s):
             if 'focus' in wconf and wconf['focus']:
                 w.select_window()
 
-            s.server._update_windows()
+            session.server._update_windows()
 
             yield w, wconf
 
@@ -349,6 +352,12 @@ def config_after_window(self, w, wconf):
             for key, val in wconf['options_after'].items():
                 w.set_window_option(key, val)
 
+    def find_current_attached_session(self):
+        return self.server.list_sessions()[0]
+
+    def first_window_pass(self, i, session, append_same_sassion):
+        return len(session.windows) == 1 and i == 1 and not append_same_sassion
+
 
 def freeze(session):
     """