diff --git a/CMakeLists.txt b/CMakeLists.txt
index 396cd13..5ee0ef9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -39,6 +39,7 @@ add_executable(${APP_NAME}
     ${SOURCE_DIR}/action.c
     ${SOURCE_DIR}/xkb.c
     ${SOURCE_DIR}/atoms.c
+    ${SOURCE_DIR}/layout.c
 )
 
 find_package(PkgConfig REQUIRED)
diff --git a/src/client.c b/src/client.c
index 365ce18..fe712d6 100644
--- a/src/client.c
+++ b/src/client.c
@@ -1,5 +1,6 @@
 #include "client.h"
 
+#include <stdint.h>
 #include <string.h>
 #include <xcb/xcb.h>
 #include <xcb/xcb_aux.h>
@@ -48,6 +49,13 @@ static void client_detach_stack(client_t *client) {
   }
 }
 
+task_in_tag_t *client_get_task_in_tag(client_t *client, tag_t *tag) {
+  for (task_in_tag_t *task = tag->task_list; task; task = task->next) {
+    if (task->client == client) return task;
+  }
+  return nullptr;
+}
+
 void client_manage(xcb_window_t window,
                    xcb_get_geometry_reply_t *geometry_reply) {
   client_t *c = p_new(client_t, 1);
@@ -104,6 +112,36 @@ void client_manage(xcb_window_t window,
   xcb_flush(wm.xcb_conn);
 }
 
+bool client_need_layout(client_t *client) {
+  if (client->floating || client->fullscreen || client->maximize ||
+      client->minimize) {
+    return false;
+  }
+  return true;
+}
+
+void client_move_to(client_t *client, int16_t x, int16_t y) {
+  client->geometry.x = x;
+  client->geometry.y = y;
+  uint16_t mask = XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y;
+  const xcb_params_configure_window_t params = {.x = x, .y = y};
+  xcb_aux_configure_window(wm.xcb_conn, client->window, mask, &params);
+  logger("== client 0x%x move to x: %d, y: %d\n", client->window, x, y);
+}
+
+void client_resize(client_t *client, uint16_t width, uint16_t height) {
+  client->geometry.width = width;
+  client->geometry.height = height;
+  uint16_t mask = XCB_CONFIG_WINDOW_WIDTH | XCB_CONFIG_WINDOW_HEIGHT;
+  const xcb_params_configure_window_t params = {
+    .width = width,
+    .height = height,
+  };
+  xcb_aux_configure_window(wm.xcb_conn, client->window, mask, &params);
+  logger("== client 0x%x resize to width: %d, height: %d\n", client->window,
+         width, height);
+}
+
 bool client_is_visible(client_t *client) {
   return client->tags & client->monitor->selected_tag->mask;
 }
diff --git a/src/client.h b/src/client.h
index 5854e47..df3e8aa 100644
--- a/src/client.h
+++ b/src/client.h
@@ -6,8 +6,10 @@
 #include "types.h"
 
 client_t *client_get_by_window(xcb_window_t window);
+task_in_tag_t *client_get_task_in_tag(client_t *client, tag_t *tag);
 void client_manage(xcb_window_t window,
                    xcb_get_geometry_reply_t *geometry_reply);
+bool client_need_layout(client_t *client);
 
 void client_send_to_tag(client_t *client, uint32_t tag_mask);
 void client_send_to_monitor(client_t *client, monitor_t *monitor);
diff --git a/src/default_config.h b/src/default_config.h
index efbc072..0702e7e 100644
--- a/src/default_config.h
+++ b/src/default_config.h
@@ -4,6 +4,7 @@
 #include <stdint.h>
 
 #include "action.h"
+#include "layout.h"
 #include "types.h"
 
 static const char *const font_family = "monospace";
@@ -35,6 +36,6 @@ static const keyboard_t key_list[] = {
 };
 
 static const layout_t layout_list[] = {
-  {.symbol = "[M]", .arrange = nullptr},
+  {.symbol = "[M]", .arrange = monocle},
   {.symbol = "><=", .arrange = nullptr},
 };
diff --git a/src/layout.c b/src/layout.c
new file mode 100644
index 0000000..5769caf
--- /dev/null
+++ b/src/layout.c
@@ -0,0 +1,19 @@
+#include "layout.h"
+
+#include <stdint.h>
+
+#include "client.h"
+#include "types.h"
+#include "utils.h"
+
+void monocle(tag_t *tag) {
+  logger("== monocle tag: %s start ==\n", tag->name);
+  for (task_in_tag_t *task = tag->task_list; task; task = task->next) {
+    if (!client_need_layout(task->client)) continue;
+    task->geometry = task->client->monitor->workarea;
+    logger("== window 0x%x: x: %d, y: %d, width: %u, height: %u\n",
+           task->client->window, task->geometry.x, task->geometry.y,
+           task->geometry.width, task->geometry.height);
+  }
+  logger("== monocle tag: %s end ==\n", tag->name);
+}
diff --git a/src/layout.h b/src/layout.h
new file mode 100644
index 0000000..bace03e
--- /dev/null
+++ b/src/layout.h
@@ -0,0 +1,5 @@
+#pragma once
+
+#include "types.h"
+
+void monocle(tag_t *tag);
diff --git a/src/monitor.c b/src/monitor.c
index 1311357..e86488d 100644
--- a/src/monitor.c
+++ b/src/monitor.c
@@ -7,6 +7,7 @@
 #include <xcb/xcb_aux.h>
 
 #include "base.h"
+#include "client.h"
 #include "color.h"
 #include "text.h"
 #include "types.h"
@@ -210,3 +211,29 @@ void monitor_draw_bar(monitor_t *monitor) {
   monitor_draw_tags(monitor);
   monitor_draw_layout_symbol(monitor);
 }
+
+void monitor_arrange(monitor_t *monitor) {
+  tag_t *tag = monitor->selected_tag;
+  if (tag->layout && tag->layout->arrange) tag->layout->arrange(tag);
+
+  for (client_t *c = wm.client_list; c; c = c->next) {
+    task_in_tag_t *task = client_get_task_in_tag(c, tag);
+    if (task) {
+      if (task->geometry.x != c->geometry.x ||
+          task->geometry.y != c->geometry.y) {
+        client_move_to(c, task->geometry.x, task->geometry.y);
+      }
+      if (task->geometry.width != c->geometry.width ||
+          task->geometry.height != c->geometry.height) {
+        client_resize(c, task->geometry.width, task->geometry.height);
+      }
+    } else {
+      int16_t x = -c->geometry.width;
+      int16_t y = -c->geometry.height;
+      if (x != c->geometry.x || y != c->geometry.y) {
+        client_move_to(c, x, y);
+      }
+    }
+  }
+  xcb_flush(wm.xcb_conn);
+}
diff --git a/src/monitor.h b/src/monitor.h
index 31b6b01..74895da 100644
--- a/src/monitor.h
+++ b/src/monitor.h
@@ -10,3 +10,4 @@ void monitor_select_tag(monitor_t *monitor, uint32_t tag_mask);
 void monitor_clean(monitor_t *monitor);
 void monitor_init_bar(monitor_t *monitor);
 void monitor_draw_bar(monitor_t *monitor);
+void monitor_arrange(monitor_t *monitor);