diff --git a/pw_console/py/BUILD.gn b/pw_console/py/BUILD.gn
index d680a49..f6e54f0 100644
--- a/pw_console/py/BUILD.gn
+++ b/pw_console/py/BUILD.gn
@@ -24,6 +24,7 @@
     "pw_console/console_app.py",
     "pw_console/help_window.py",
     "pw_console/key_bindings.py",
+    "pw_console/repl_pane.py",
     "pw_console/style.py",
   ]
   tests = [
diff --git a/pw_console/py/pw_console/repl_pane.py b/pw_console/py/pw_console/repl_pane.py
new file mode 100644
index 0000000..5d301ca
--- /dev/null
+++ b/pw_console/py/pw_console/repl_pane.py
@@ -0,0 +1,267 @@
+# Copyright 2021 The Pigweed Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+"""ReplPane class."""
+
+import logging
+from functools import partial
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    List,
+    Optional,
+)
+
+from prompt_toolkit.filters import (
+    Condition,
+    has_focus,
+)
+from prompt_toolkit.mouse_events import MouseEvent, MouseEventType
+from prompt_toolkit.layout.dimension import AnyDimension
+from prompt_toolkit.widgets import TextArea
+from prompt_toolkit.layout import (
+    ConditionalContainer,
+    Dimension,
+    Float,
+    FloatContainer,
+    FormattedTextControl,
+    HSplit,
+    VSplit,
+    Window,
+    WindowAlign,
+)
+from prompt_toolkit.lexers import PygmentsLexer  # type: ignore
+from pygments.lexers.python import PythonLexer  # type: ignore
+
+_LOG = logging.getLogger(__package__)
+
+_Namespace = Dict[str, Any]
+_GetNamespace = Callable[[], _Namespace]
+
+
+def mouse_focus_handler(repl_pane, mouse_event: MouseEvent):
+    """Focus the repl_pane on click."""
+    if not has_focus(repl_pane)():
+        if mouse_event.event_type == MouseEventType.MOUSE_UP:
+            repl_pane.application.application.layout.focus(repl_pane)
+            return None
+    return NotImplemented
+
+
+class FocusOnClickFloatContainer(ConditionalContainer):
+    """Empty container rendered if the repl_pane is not in focus.
+
+    This container should be rendered with transparent=True so nothing is shown
+    to the user. Container is not rendered if the repl_pane is already in focus.
+    """
+    def __init__(self, repl_pane):
+
+        empty_text = FormattedTextControl([(
+            # Style
+            '',
+            # Text
+            ' ',
+            # Mouse handler
+            partial(mouse_focus_handler, repl_pane),
+        )])
+
+        super().__init__(
+            Window(empty_text),
+            filter=Condition(lambda: not has_focus(repl_pane)()),
+        )
+
+
+class ReplPaneBottomToolbarBar(ConditionalContainer):
+    """Repl pane bottom toolbar."""
+    @staticmethod
+    def get_center_text_tokens(repl_pane):
+        """Return toolbar text showing if the ReplPane is in focus or not."""
+        focused_text = (
+            # Style
+            "",
+            # Text
+            " [FOCUSED] ",
+            # Mouse handler
+            partial(mouse_focus_handler, repl_pane),
+        )
+
+        out_of_focus_text = (
+            # Style
+            'class:keyhelp',
+            # Text
+            ' [click to focus] ',
+            # Mouse handler
+            partial(mouse_focus_handler, repl_pane),
+        )
+
+        if has_focus(repl_pane)():
+            return [focused_text]
+        return [out_of_focus_text]
+
+    def __init__(self, repl_pane):
+        left_section_text = FormattedTextControl([(
+            # Style
+            'class:logo',
+            # Text
+            ' Python Input ',
+            # Mouse handler
+            partial(mouse_focus_handler, repl_pane),
+        )])
+
+        center_section_text = FormattedTextControl(
+            # Callable to get formatted text tuples.
+            partial(ReplPaneBottomToolbarBar.get_center_text_tokens,
+                    repl_pane))
+
+        right_section_text = FormattedTextControl([(
+            # Style
+            'class:bottom_toolbar_colored_text',
+            # Text
+            ' [Enter]: run code ',
+        )])
+
+        left_section_window = Window(
+            content=left_section_text,
+            align=WindowAlign.LEFT,
+            dont_extend_width=True,
+        )
+
+        center_section_window = Window(
+            content=center_section_text,
+            # Center text is left justified to appear just right of the left
+            # section text.
+            align=WindowAlign.LEFT,
+            # Expand center section to fill space between the left and right
+            # side of the toolbar.
+            dont_extend_width=False,
+        )
+
+        right_section_window = Window(
+            content=right_section_text,
+            # Right side text should appear at the far right of the toolbar
+            align=WindowAlign.RIGHT,
+            dont_extend_width=True,
+        )
+
+        toolbar_vsplit = VSplit(
+            [
+                left_section_window,
+                center_section_window,
+                right_section_window,
+            ],
+            height=1,
+            style='class:bottom_toolbar',
+            align=WindowAlign.LEFT,
+        )
+
+        super().__init__(
+            # Content
+            toolbar_vsplit,
+            filter=Condition(lambda: repl_pane.show_bottom_toolbar))
+
+
+class ReplPane:
+    """Pane for reading Python input."""
+
+    # pylint: disable=too-many-instance-attributes,too-few-public-methods
+    def __init__(
+            self,
+            application: Any,
+            # TODO: Include ptpython repl.
+            # python_repl: PwPtPythonRepl,
+            # TODO: Make the height of input+output windows match the log pane
+            # height. (Using minimum output height of 5 for now).
+            output_height: Optional[AnyDimension] = Dimension(preferred=5),
+            # TODO: Figure out how to resize ptpython input field.
+            _input_height: Optional[AnyDimension] = None,
+            # Default width and height to 50% of the screen
+            height: Optional[AnyDimension] = Dimension(weight=50),
+            width: Optional[AnyDimension] = Dimension(weight=50),
+    ) -> None:
+        self.height = height
+        self.width = width
+
+        self.executed_code: List = []
+        self.application = application
+        self.show_top_toolbar = True
+        self.show_bottom_toolbar = True
+
+        # TODO: Include ptpython repl.
+        self.pw_ptpython_repl = Window(content=FormattedTextControl(
+            [('', '>>> Repl input buffer')], focusable=True))
+        self.last_error_output = ""
+
+        self.output_field = TextArea(
+            text='Repl output buffer',
+            style='class:output-field',
+            height=output_height,
+            # text=help_text,
+            focusable=False,
+            scrollbar=True,
+            lexer=PygmentsLexer(PythonLexer),
+        )
+
+        self.bottom_toolbar = ReplPaneBottomToolbarBar(self)
+
+        # ReplPane root container
+        self.container = FloatContainer(
+            # Horizontal split of all Repl pane sections.
+            HSplit(
+                [
+                    # 1. Repl Output
+                    self.output_field,
+                    # 2. Static separator toolbar.
+                    Window(
+                        content=FormattedTextControl([(
+                            # Style
+                            'class:logo',
+                            # Text
+                            ' Python Results ',
+                        )]),
+                        height=1,
+                        style='class:menu-bar'),
+                    # 3. Repl Input
+                    self.pw_ptpython_repl,
+                    # 4. Bottom toolbar
+                    self.bottom_toolbar,
+                ],
+                height=self.height,
+                width=self.width,
+            ),
+            floats=[
+                # Transparent float container that will focus on the repl_pane
+                # when clicked. It is hidden if already in focus.
+                Float(
+                    FocusOnClickFloatContainer(self),
+                    transparent=True,
+                    # Full size of the ReplPane minus one line for the bottom
+                    # toolbar.
+                    right=0,
+                    left=0,
+                    top=0,
+                    bottom=1,
+                ),
+            ])
+
+    def __pt_container__(self):
+        """Return the prompt_toolkit container for this ReplPane."""
+        return self.container
+
+    # pylint: disable=no-self-use
+    def get_all_key_bindings(self) -> List:
+        """Return all keybinds for this plugin."""
+        return []
+
+    def after_render_hook(self):
+        """Run tasks after the last UI render."""