diff --git a/CHANGES b/CHANGES
index da82a88aa..c9a99b0c3 100644
--- a/CHANGES
+++ b/CHANGES
@@ -14,10 +14,57 @@ $ pip install --user --upgrade --pre libtmux
 
 <!-- Maintainers and contributors: Insert change notes for the next release above -->
 
+### Breaking changes
+
+#### `Session.new_window()` + `Window.split_window()`: No longer attaches by default
+
+- 0.28 +: Now _defaults_ to `attach=False`.
+- 0.27.1 and before: _defaults_ to `attach=True`.
+
+Pass `attach=True` for the old behavior.
+
+#### `Pane.resize_pane()` renamed to `Pane.resize()`: (#523)
+
+This convention will be more consistent with `Window.resize()`.
+
+#### `Pane.resize_pane()`: Params changed (#523)
+
+- No longer accepts `-U`, `-D`, `-L`, `-R` directly, instead accepts
+  `ResizeAdjustmentDirection`.
+
+### New features
+
+#### `Pane.resize()`: Improved param coverage (#523)
+
+- Learned to accept adjustments via `adjustment_direction` w/
+  `ResizeAdjustmentDirection` + `adjustment`.
+
+- Learned to accept manual `height` and / or `width` (columns/rows or percentage)
+
+- Zoom (and unzoom)
+
+#### `Window.resize_window()`: New Method (#523)
+
+If `Pane.resize_pane()` (now `Pane.resize()`) didn't work before, try resizing the window.
+
+### Bug fixes
+
+#### `Window.refresh()` and `Pane.refresh()`: Refresh more underlying state (#523)
+
+#### `Obj._refresh`: Allow passing args (#523)
+
+e.g. `-a` (all) to `list-panes` and `list-windows`
+
+#### `Server.panes`: Fix listing of panes (#523)
+
+Would list only panes in attached session, rather than all in a server.
+
 ### Improvement
 
 - Pane, Window: Improve parsing of option values that return numbers
   (#520)
+- `Obj._refresh`: Allow passing `list_extra_args` to ensure `list-windows` and
+  `list-panes` can return more than the target (#523)
 
 ### Tests
 
diff --git a/docs/reference/constants.md b/docs/reference/constants.md
new file mode 100644
index 000000000..67d56ac91
--- /dev/null
+++ b/docs/reference/constants.md
@@ -0,0 +1,6 @@
+# Constants
+
+```{eval-rst}
+.. automodule:: libtmux.constants
+   :members:
+```
diff --git a/docs/reference/index.md b/docs/reference/index.md
index 2a6c9ff63..99d614fee 100644
--- a/docs/reference/index.md
+++ b/docs/reference/index.md
@@ -11,6 +11,7 @@ servers
 sessions
 windows
 panes
+constants
 common
 exceptions
 ```
diff --git a/src/libtmux/__init__.py b/src/libtmux/__init__.py
index 4c2847c93..7dd7284f6 100644
--- a/src/libtmux/__init__.py
+++ b/src/libtmux/__init__.py
@@ -1,4 +1,4 @@
-# flake8: NOQA
+"""libtmux, a typed, pythonic API wrapper for the tmux terminal multiplexer."""
 from .__about__ import (
     __author__,
     __copyright__,
diff --git a/src/libtmux/common.py b/src/libtmux/common.py
index c8bb6ccc4..46ad57d4a 100644
--- a/src/libtmux/common.py
+++ b/src/libtmux/common.py
@@ -1,4 +1,3 @@
-# flake8: NOQA: W605
 """Helper methods and mixins for libtmux.
 
 libtmux.common
diff --git a/src/libtmux/constants.py b/src/libtmux/constants.py
new file mode 100644
index 000000000..6411ebb6b
--- /dev/null
+++ b/src/libtmux/constants.py
@@ -0,0 +1,20 @@
+"""Constant variables for libtmux."""
+import enum
+import typing as t
+
+
+class ResizeAdjustmentDirection(enum.Enum):
+    """Used for *adjustment* in ``resize_window``, ``resize_pane``."""
+
+    Up = "UP"
+    Down = "DOWN"
+    Left = "LEFT"
+    Right = "RIGHT"
+
+
+RESIZE_ADJUSTMENT_DIRECTION_FLAG_MAP: t.Dict[ResizeAdjustmentDirection, str] = {
+    ResizeAdjustmentDirection.Up: "-U",
+    ResizeAdjustmentDirection.Down: "-D",
+    ResizeAdjustmentDirection.Left: "-L",
+    ResizeAdjustmentDirection.Right: "-R",
+}
diff --git a/src/libtmux/exc.py b/src/libtmux/exc.py
index c77604599..cf31575f7 100644
--- a/src/libtmux/exc.py
+++ b/src/libtmux/exc.py
@@ -132,3 +132,33 @@ class NoWindowsExist(WindowError):
 
     def __init__(self, *args: object):
         return super().__init__("No windows exist for object")
+
+
+class AdjustmentDirectionRequiresAdjustment(LibTmuxException, ValueError):
+    """If *adjustment_direction* is set, *adjustment* must be set."""
+
+    def __init__(self) -> None:
+        super().__init__("adjustment_direction requires adjustment")
+
+
+class WindowAdjustmentDirectionRequiresAdjustment(
+    WindowError, AdjustmentDirectionRequiresAdjustment
+):
+    """ValueError for :meth:`libtmux.Window.resize_window`."""
+
+    pass
+
+
+class PaneAdjustmentDirectionRequiresAdjustment(
+    WindowError, AdjustmentDirectionRequiresAdjustment
+):
+    """ValueError for :meth:`libtmux.Pane.resize_pane`."""
+
+    pass
+
+
+class RequiresDigitOrPercentage(LibTmuxException, ValueError):
+    """Requires digit (int or str digit) or a percentage."""
+
+    def __init__(self) -> None:
+        super().__init__("Requires digit (int or str digit) or a percentage.")
diff --git a/src/libtmux/neo.py b/src/libtmux/neo.py
index 926da8254..af8a0062b 100644
--- a/src/libtmux/neo.py
+++ b/src/libtmux/neo.py
@@ -167,12 +167,14 @@ def _refresh(
         obj_key: str,
         obj_id: str,
         list_cmd: "ListCmd" = "list-panes",
+        list_extra_args: "t.Optional[ListExtraArgs]" = None,
     ) -> None:
         assert isinstance(obj_id, str)
         obj = fetch_obj(
             obj_key=obj_key,
             obj_id=obj_id,
             list_cmd=list_cmd,
+            list_extra_args=list_extra_args,
             server=self.server,
         )
         assert obj is not None
diff --git a/src/libtmux/pane.py b/src/libtmux/pane.py
index c9b5b7cc2..a2eeea33b 100644
--- a/src/libtmux/pane.py
+++ b/src/libtmux/pane.py
@@ -1,4 +1,3 @@
-# flake8: NOQA: W605
 """Pythonization of the :ref:`tmux(1)` pane.
 
 libtmux.pane
@@ -11,7 +10,11 @@
 import warnings
 from typing import overload
 
-from libtmux.common import tmux_cmd
+from libtmux.common import has_gte_version, tmux_cmd
+from libtmux.constants import (
+    RESIZE_ADJUSTMENT_DIRECTION_FLAG_MAP,
+    ResizeAdjustmentDirection,
+)
 from libtmux.neo import Obj, fetch_obj
 
 from . import exc
@@ -71,7 +74,11 @@ class Pane(Obj):
     def refresh(self) -> None:
         """Refresh pane attributes from tmux."""
         assert isinstance(self.pane_id, str)
-        return super()._refresh(obj_key="pane_id", obj_id=self.pane_id)
+        return super()._refresh(
+            obj_key="pane_id",
+            obj_id=self.pane_id,
+            list_extra_args=("-a",),
+        )
 
     @classmethod
     def from_pane_id(cls, server: "Server", pane_id: str) -> "Pane":
@@ -122,31 +129,99 @@ def cmd(self, cmd: str, *args: t.Any, **kwargs: t.Any) -> tmux_cmd:
     Commands (tmux-like)
     """
 
-    def resize_pane(self, *args: t.Any, **kwargs: t.Any) -> "Pane":
+    def resize(
+        self,
+        # Adjustments
+        adjustment_direction: t.Optional[ResizeAdjustmentDirection] = None,
+        adjustment: t.Optional[int] = None,
+        # Manual
+        height: t.Optional[t.Union[str, int]] = None,
+        width: t.Optional[t.Union[str, int]] = None,
+        # Zoom
+        zoom: t.Optional[bool] = None,
+        # Mouse
+        mouse: t.Optional[bool] = None,
+        # Optional flags
+        trim_below: t.Optional[bool] = None,
+    ) -> "Pane":
         """Resize tmux pane.
 
         Parameters
         ----------
-        target_pane : str
-            ``target_pane``, or ``-U``,``-D``, ``-L``, ``-R``.
+        adjustment_direction : ResizeAdjustmentDirection, optional
+            direction to adjust, ``Up``, ``Down``, ``Left``, ``Right``.
+        adjustment : ResizeAdjustmentDirection, optional
 
-        Other Parameters
-        ----------------
-        height : int
+        height : int, optional
             ``resize-pane -y`` dimensions
-        width : int
+        width : int, optional
             ``resize-pane -x`` dimensions
 
+        zoom : bool
+            expand pane
+
+        mouse : bool
+            resize via mouse
+
+        trim_below : bool
+            trim below cursor
+
         Raises
         ------
-        exc.LibTmuxException
+        :exc:`exc.LibTmuxException`,
+        :exc:`exc.PaneAdjustmentDirectionRequiresAdjustment`,
+        :exc:`exc.RequiresDigitOrPercentage`
+
+        Returns
+        -------
+        :class:`Pane`
+
+        Notes
+        -----
+        Three types of resizing are available:
+
+        1. Adjustments: ``adjustment_direction`` and ``adjustment``.
+        2. Manual resizing: ``height`` and / or ``width``.
+        3. Zoom / Unzoom: ``zoom``.
         """
-        if "height" in kwargs:
-            proc = self.cmd("resize-pane", "-y%s" % int(kwargs["height"]))
-        elif "width" in kwargs:
-            proc = self.cmd("resize-pane", "-x%s" % int(kwargs["width"]))
-        else:
-            proc = self.cmd("resize-pane", args[0])
+        tmux_args: t.Tuple[str, ...] = ()
+
+        ## Adjustments
+        if adjustment_direction:
+            if adjustment is None:
+                raise exc.PaneAdjustmentDirectionRequiresAdjustment()
+            tmux_args += (
+                f"{RESIZE_ADJUSTMENT_DIRECTION_FLAG_MAP[adjustment_direction]}",
+                str(adjustment),
+            )
+        elif height or width:
+            ## Manual resizing
+            if height:
+                if isinstance(height, str):
+                    if height.endswith("%") and not has_gte_version("3.1"):
+                        raise exc.VersionTooLow
+                    if not height.isdigit() and not height.endswith("%"):
+                        raise exc.RequiresDigitOrPercentage
+                tmux_args += (f"-y{height}",)
+
+            if width:
+                if isinstance(width, str):
+                    if width.endswith("%") and not has_gte_version("3.1"):
+                        raise exc.VersionTooLow
+                    if not width.isdigit() and not width.endswith("%"):
+                        raise exc.RequiresDigitOrPercentage
+
+                tmux_args += (f"-x{width}",)
+        elif zoom:
+            ## Zoom / Unzoom
+            tmux_args += ("-Z",)
+        elif mouse:
+            tmux_args += ("-M",)
+
+        if trim_below:
+            tmux_args += ("-T",)
+
+        proc = self.cmd("resize-pane", *tmux_args)
 
         if proc.stderr:
             raise exc.LibTmuxException(proc.stderr)
@@ -442,7 +517,7 @@ def get(self, key: str, default: t.Optional[t.Any] = None) -> t.Any:
 
         .. deprecated:: 0.16
 
-           Deprecated by attribute lookup.e.g. ``pane['window_name']`` is now
+           Deprecated by attribute lookup, e.g. ``pane['window_name']`` is now
            accessed via ``pane.window_name``.
 
         """
@@ -460,3 +535,38 @@ def __getitem__(self, key: str) -> t.Any:
         """
         warnings.warn(f"Item lookups, e.g. pane['{key}'] is deprecated", stacklevel=2)
         return getattr(self, key)
+
+    def resize_pane(
+        self,
+        # Adjustments
+        adjustment_direction: t.Optional[ResizeAdjustmentDirection] = None,
+        adjustment: t.Optional[int] = None,
+        # Manual
+        height: t.Optional[t.Union[str, int]] = None,
+        width: t.Optional[t.Union[str, int]] = None,
+        # Zoom
+        zoom: t.Optional[bool] = None,
+        # Mouse
+        mouse: t.Optional[bool] = None,
+        # Optional flags
+        trim_below: t.Optional[bool] = None,
+    ) -> "Pane":
+        """Resize pane, deprecated by :meth:`Pane.resize`.
+
+        .. deprecated:: 0.28
+
+           Deprecated by :meth:`Pane.resize`.
+        """
+        warnings.warn(
+            "Deprecated: Use Pane.resize() instead of Pane.resize_pane()",
+            stacklevel=2,
+        )
+        return self.resize(
+            adjustment_direction=adjustment_direction,
+            adjustment=adjustment,
+            height=height,
+            width=width,
+            zoom=zoom,
+            mouse=mouse,
+            trim_below=trim_below,
+        )
diff --git a/src/libtmux/pytest_plugin.py b/src/libtmux/pytest_plugin.py
index 7cd44c91c..2819b33e5 100644
--- a/src/libtmux/pytest_plugin.py
+++ b/src/libtmux/pytest_plugin.py
@@ -217,7 +217,9 @@ def session(
     session_name = "tmuxp"
 
     if not server.has_session(session_name):
-        server.cmd("new-session", "-d", "-s", session_name)
+        server.new_session(
+            session_name=session_name,
+        )
 
     # find current sessions prefixed with tmuxp
     old_test_sessions = []
@@ -228,7 +230,10 @@ def session(
 
     TEST_SESSION_NAME = get_test_session_name(server=server)
 
-    session = server.new_session(session_name=TEST_SESSION_NAME, **session_params)
+    session = server.new_session(
+        session_name=TEST_SESSION_NAME,
+        **session_params,
+    )
 
     """
     Make sure that tmuxp can :ref:`test_builder_visually` and switches to
diff --git a/src/libtmux/server.py b/src/libtmux/server.py
index 8e12041a4..ec9ef384d 100644
--- a/src/libtmux/server.py
+++ b/src/libtmux/server.py
@@ -542,7 +542,7 @@ def panes(self) -> QueryList[Pane]:
             Pane(server=self, **obj)
             for obj in fetch_objs(
                 list_cmd="list-panes",
-                list_extra_args=["-s"],
+                list_extra_args=("-a",),
                 server=self,
             )
         ]
diff --git a/src/libtmux/session.py b/src/libtmux/session.py
index 9ea495779..6e2aa059b 100644
--- a/src/libtmux/session.py
+++ b/src/libtmux/session.py
@@ -436,7 +436,7 @@ def new_window(
         self,
         window_name: t.Optional[str] = None,
         start_directory: None = None,
-        attach: bool = True,
+        attach: bool = False,
         window_index: str = "",
         window_shell: t.Optional[str] = None,
         environment: t.Optional[t.Dict[str, str]] = None,
@@ -465,6 +465,10 @@ def new_window(
                 useful for long-running processes where the closing of the
                 window upon completion is desired.
 
+        .. versionchanged:: 0.28.0
+
+           ``attach`` default changed from ``True`` to ``False``.
+
         Returns
         -------
         :class:`Window`
diff --git a/src/libtmux/window.py b/src/libtmux/window.py
index 98401f0bd..b5b6bbcbe 100644
--- a/src/libtmux/window.py
+++ b/src/libtmux/window.py
@@ -13,6 +13,10 @@
 
 from libtmux._internal.query_list import QueryList
 from libtmux.common import has_gte_version, tmux_cmd
+from libtmux.constants import (
+    RESIZE_ADJUSTMENT_DIRECTION_FLAG_MAP,
+    ResizeAdjustmentDirection,
+)
 from libtmux.neo import Obj, fetch_obj, fetch_objs
 from libtmux.pane import Pane
 
@@ -39,7 +43,7 @@ class Window(Obj):
 
     Examples
     --------
-    >>> window = session.new_window('My project')
+    >>> window = session.new_window('My project', attach=True)
 
     >>> window
     Window(@2 2:My project, Session($... ...))
@@ -85,6 +89,7 @@ def refresh(self) -> None:
             obj_key="window_id",
             obj_id=self.window_id,
             list_cmd="list-windows",
+            list_extra_args=("-a",),
         )
 
     @classmethod
@@ -158,8 +163,8 @@ def select_pane(self, target_pane: t.Union[str, int]) -> t.Optional["Pane"]:
         target_pane : str
             'target_pane', '-U' ,'-D', '-L', '-R', or '-l'.
 
-        Return
-        ------
+        Returns
+        -------
         :class:`Pane`
         """
         if target_pane in ["-l", "-U", "-D", "-L", "-R"]:
@@ -176,7 +181,7 @@ def split_window(
         self,
         target: t.Optional[t.Union[int, str]] = None,
         start_directory: t.Optional[str] = None,
-        attach: bool = True,
+        attach: bool = False,
         vertical: bool = True,
         shell: t.Optional[str] = None,
         percent: t.Optional[int] = None,
@@ -219,6 +224,10 @@ def split_window(
         By default, this will make the window the pane is created in
         active. To remain on the same window and split the pane in another
         target window, pass in ``attach=False``.
+
+        .. versionchanged:: 0.28.0
+
+           ``attach`` default changed from ``True`` to ``False``.
         """
         tmux_formats = ["#{pane_id}" + FORMAT_SEPARATOR]
 
@@ -279,6 +288,87 @@ def split_window(
 
         return Pane.from_pane_id(server=self.server, pane_id=pane_formatters["pane_id"])
 
+    def resize(
+        self,
+        # Adjustments
+        adjustment_direction: t.Optional[ResizeAdjustmentDirection] = None,
+        adjustment: t.Optional[int] = None,
+        # Manual
+        height: t.Optional[int] = None,
+        width: t.Optional[int] = None,
+        # Expand / Shrink
+        expand: t.Optional[bool] = None,
+        shrink: t.Optional[bool] = None,
+    ) -> "Window":
+        """Resize tmux window.
+
+        Parameters
+        ----------
+        adjustment_direction : ResizeAdjustmentDirection, optional
+            direction to adjust, ``Up``, ``Down``, ``Left``, ``Right``.
+        adjustment : ResizeAdjustmentDirection, optional
+
+        height : int, optional
+            ``resize-window -y`` dimensions
+        width : int, optional
+            ``resize-window -x`` dimensions
+
+        expand : bool
+            expand window
+        shrink : bool
+            shrink window
+
+        Raises
+        ------
+        :exc:`exc.LibTmuxException`,
+        :exc:`exc.PaneAdjustmentDirectionRequiresAdjustment`
+
+        Returns
+        -------
+        :class:`Window`
+
+        Notes
+        -----
+        Three types of resizing are available:
+
+        1. Adjustments: ``adjustment_direction`` and ``adjustment``.
+        2. Manual resizing: ``height`` and / or ``width``.
+        3. Expand or shrink: ``expand`` or ``shrink``.
+        """
+        if not has_gte_version("2.9"):
+            warnings.warn("resize() requires tmux 2.9 or newer", stacklevel=2)
+            return self
+
+        tmux_args: t.Tuple[str, ...] = ()
+
+        ## Adjustments
+        if adjustment_direction:
+            if adjustment is None:
+                raise exc.WindowAdjustmentDirectionRequiresAdjustment()
+            tmux_args += (
+                f"{RESIZE_ADJUSTMENT_DIRECTION_FLAG_MAP[adjustment_direction]}",
+                str(adjustment),
+            )
+        elif height or width:
+            ## Manual resizing
+            if height:
+                tmux_args += (f"-y{int(height)}",)
+            if width:
+                tmux_args += (f"-x{int(width)}",)
+        elif expand or shrink:
+            if expand:
+                tmux_args += ("-A",)
+            elif shrink:
+                tmux_args += ("-a",)
+
+        proc = self.cmd("resize-window", *tmux_args)
+
+        if proc.stderr:
+            raise exc.LibTmuxException(proc.stderr)
+
+        self.refresh()
+        return self
+
     def last_pane(self) -> t.Optional["Pane"]:
         """Return last pane."""
         return self.select_pane("-l")
diff --git a/tests/test_dataclasses.py b/tests/test_dataclasses.py
index a8dcdf517..65f80faf4 100644
--- a/tests/test_dataclasses.py
+++ b/tests/test_dataclasses.py
@@ -9,6 +9,7 @@
     ObjectDoesNotExist,
     QueryList,
 )
+from libtmux.constants import ResizeAdjustmentDirection
 from libtmux.pane import Pane
 from libtmux.server import Server
 from libtmux.session import Session
@@ -40,11 +41,9 @@ def test_pane(
 
     __window = __session.attached_window
     __window.split_window()
-    __window.split_window()
+    __pane = __window.split_window()
     __window.select_layout("main-vertical")
 
-    __pane = __window.attached_pane
-
     assert __pane is not None
     assert __pane.pane_id is not None
 
@@ -61,8 +60,10 @@ def test_pane(
 
     old_pane_size = pane.pane_height
 
-    pane.resize_pane("-D", 25)
-    pane.resize_pane("-R", 25)
+    pane.resize_pane(adjustment_direction=ResizeAdjustmentDirection.Down, adjustment=25)
+    pane.resize_pane(
+        adjustment_direction=ResizeAdjustmentDirection.Right, adjustment=25
+    )
 
     assert old_pane_size != pane.pane_height
     assert pane.pane_current_command is not None
diff --git a/tests/test_pane.py b/tests/test_pane.py
index 3ca421c69..f05528a9e 100644
--- a/tests/test_pane.py
+++ b/tests/test_pane.py
@@ -2,31 +2,15 @@
 import logging
 import shutil
 
+import pytest
+
+from libtmux.common import has_gte_version, has_lt_version
+from libtmux.constants import ResizeAdjustmentDirection
 from libtmux.session import Session
 
 logger = logging.getLogger(__name__)
 
 
-def test_resize_pane(session: Session) -> None:
-    """Test Pane.resize_pane()."""
-    window = session.attached_window
-    window.rename_window("test_resize_pane")
-
-    pane1 = window.attached_pane
-    assert pane1 is not None
-    pane1_height = pane1.pane_height
-    window.split_window()
-
-    pane1.resize_pane(height=4)
-    assert pane1.pane_height != pane1_height
-    assert pane1.pane_height is not None
-    assert int(pane1.pane_height) == 4
-
-    pane1.resize_pane(height=3)
-    assert pane1.pane_height is not None
-    assert int(pane1.pane_height) == 3
-
-
 def test_send_keys(session: Session) -> None:
     """Verify Pane.send_keys()."""
     pane = session.attached_window.attached_pane
@@ -146,3 +130,95 @@ def test_capture_pane_end(session: Session) -> None:
     assert pane_contents == '$ printf "%s"'
     pane_contents = "\n".join(pane.capture_pane(end="-"))
     assert pane_contents == '$ printf "%s"\n$'
+
+
+@pytest.mark.skipif(
+    has_lt_version("2.9"),
+    reason="resize-window only exists in tmux 2.9+",
+)
+def test_resize_pane(
+    session: Session,
+) -> None:
+    """Verify resizing window."""
+    session.cmd("detach-client", "-s")
+
+    window = session.attached_window
+    pane = window.split_window(attach=False)
+    window.split_window(vertical=True, attach=False)
+
+    assert pane is not None
+
+    window.resize(height=500, width=500)
+
+    pane_height_adjustment = 10
+
+    assert pane.pane_height is not None
+    assert pane.pane_width is not None
+
+    #
+    # Manual resizing
+    #
+
+    # Manual: Height
+    pane_height_before = int(pane.pane_height)
+    pane.resize_pane(
+        height="50",
+    )
+    assert int(pane.pane_height) == 50
+
+    # Manual: Width
+    window.select_layout("main-horizontal")
+    pane.resize_pane(
+        width="75",
+    )
+    assert int(pane.pane_width) == 75
+
+    if has_gte_version("3.1"):
+        # Manual: Height percentage
+        window.select_layout("main-vertical")
+        pane_height_before = int(pane.pane_height)
+        pane.resize_pane(
+            height="15%",
+        )
+        assert int(pane.pane_height) == 75
+
+        # Manual: Width percentage
+        window.select_layout("main-horizontal")
+        pane.resize_pane(
+            width="15%",
+        )
+        assert int(pane.pane_width) == 75
+
+    #
+    # Adjustments
+    #
+
+    # Adjustment: Down
+    pane_height_before = int(pane.pane_height)
+    pane.resize_pane(
+        adjustment_direction=ResizeAdjustmentDirection.Down,
+        adjustment=pane_height_adjustment * 2,
+    )
+    assert pane_height_before - (pane_height_adjustment * 2) == int(pane.pane_height)
+
+    # Adjustment: Up
+    pane_height_before = int(pane.pane_height)
+    pane.resize_pane(
+        adjustment_direction=ResizeAdjustmentDirection.Up,
+        adjustment=pane_height_adjustment,
+    )
+    assert pane_height_before + pane_height_adjustment == int(pane.pane_height)
+
+    #
+    # Zoom
+    #
+    pane.resize_pane(height=50)
+
+    # Zoom
+    pane.resize_pane(height=2)
+    pane_height_before = int(pane.pane_height)
+    pane.resize_pane(
+        zoom=True,
+    )
+    pane_height_expanded = int(pane.pane_height)
+    assert pane_height_before < pane_height_expanded
diff --git a/tests/test_window.py b/tests/test_window.py
index 47ec07205..4252f8469 100644
--- a/tests/test_window.py
+++ b/tests/test_window.py
@@ -9,6 +9,7 @@
 from libtmux import exc
 from libtmux._internal.query_list import ObjectDoesNotExist
 from libtmux.common import has_gte_version, has_lt_version
+from libtmux.constants import ResizeAdjustmentDirection
 from libtmux.pane import Pane
 from libtmux.server import Server
 from libtmux.session import Session
@@ -397,3 +398,83 @@ def test_split_window_with_environment_logs_warning_for_old_tmux(
     assert any(
         "Cannot set up environment" in record.msg for record in caplog.records
     ), "Warning missing"
+
+
+@pytest.mark.skipif(
+    has_lt_version("2.9"),
+    reason="resize-window only exists in tmux 2.9+",
+)
+def test_resize(
+    session: Session,
+) -> None:
+    """Verify resizing window."""
+    session.cmd("detach-client", "-s")
+
+    window = session.attached_window
+    window_height_adjustment = 10
+
+    assert window.window_height is not None
+    assert window.window_width is not None
+
+    #
+    # Manual resizing
+    #
+
+    # Manual: Height
+    window_height_before = int(window.window_height)
+    window.resize(
+        height=10,
+    )
+    assert int(window.window_height) == 10
+
+    # Manual: Width
+    window.resize(
+        width=10,
+    )
+    assert int(window.window_width) == 10
+
+    #
+    # Adjustments
+    #
+
+    # Adjustment: Down
+    window_height_before = int(window.window_height)
+    window.resize(
+        adjustment_direction=ResizeAdjustmentDirection.Down,
+        adjustment=window_height_adjustment * 2,
+    )
+    assert window_height_before + (window_height_adjustment * 2) == int(
+        window.window_height
+    )
+
+    # Adjustment: Up
+    window_height_before = int(window.window_height)
+    window.resize(
+        adjustment_direction=ResizeAdjustmentDirection.Up,
+        adjustment=window_height_adjustment,
+    )
+    assert window_height_before - window_height_adjustment == int(window.window_height)
+
+    #
+    # Shrink and expand
+    #
+    window.resize(height=50)
+
+    # Shrink
+    window_height_before = int(window.window_height)
+    window.resize(
+        shrink=True,
+    )
+    window_height_shrunk = int(window.window_height)
+    assert window_height_before > window_height_shrunk
+
+    assert window
+
+    # Expand
+    window.resize(height=2)
+    window_height_before = int(window.window_height)
+    window.resize(
+        expand=True,
+    )
+    window_height_expanded = int(window.window_height)
+    assert window_height_before < window_height_expanded