diff --git a/dock_panel.go b/dock_panel.go
new file mode 100644
index 0000000..8d34e49
--- /dev/null
+++ b/dock_panel.go
@@ -0,0 +1,193 @@
+package mujica
+
+import (
+	"fmt"
+	"log/slog"
+	"slices"
+
+	"github.com/egoist/mygo/ui"
+
+	"mujicaui/theme"
+)
+
+// DockZone is an area of a DockPanel.
+type DockZone int
+
+const (
+	DockCenter DockZone = iota
+	DockLeft
+	DockRight
+	DockBottom
+)
+
+// DockLayout is the caller-held arrangement: panel IDs per zone in tab order, and each zone's shown tab.
+type DockLayout struct {
+	Zones  [4][]string
+	Active [4]string
+}
+
+// DockItem is one dockable panel.
+type DockItem struct {
+	ID, Title string
+	Build     func()
+}
+
+// DockPanelOptions configure a DockPanel.
+type DockPanelOptions struct {
+	Disabled bool
+}
+
+// dockPanelDrag is a tab being dragged.
+type dockPanelDrag struct{ id string }
+
+// DockPanel arranges panels in left, center, right and bottom zones; tabs drag to an edge or zone to dock there.
+func DockPanel(c *ui.Context, layout *DockLayout, items []DockItem, opts DockPanelOptions) ChoiceResult {
+	if layout == nil || len(items) == 0 {
+		panic("mujica: DockPanel needs a layout and items")
+	}
+	byID := map[string]DockItem{}
+	for _, it := range items {
+		if it.ID == "" || it.Title == "" || it.Build == nil {
+			panic("mujica: DockPanel item needs an ID, Title and Build")
+		}
+		if _, dup := byID[it.ID]; dup {
+			panic("mujica: DockPanel item ID repeated: " + it.ID)
+		}
+		byID[it.ID] = it
+	}
+	placed := map[string]bool{}
+	for z, ids := range layout.Zones {
+		for _, id := range ids {
+			if _, ok := byID[id]; !ok || placed[id] {
+				panic(fmt.Sprintf("mujica: DockPanel zone %d holds unknown or repeated %q", z, id))
+			}
+			placed[id] = true
+		}
+	}
+	changed := false
+	for _, it := range items {
+		if !placed[it.ID] {
+			layout.Zones[DockCenter] = append(layout.Zones[DockCenter], it.ID)
+			changed = true
+		}
+	}
+	for z, ids := range layout.Zones {
+		if len(ids) > 0 && !slices.Contains(ids, layout.Active[z]) {
+			layout.Active[z] = ids[0]
+		}
+	}
+	k := Tokens(c)
+	u := Density(c).Unit()
+	root := ui.Box(c).Disabled(opts.Disabled).MinHeight(0)
+	disabled := root.IsDisabled()
+	// follow is the tab that moved; it keeps the focus in its new zone.
+	follow := ui.Local(root, "dock_panel.follow", func() string { return "" })
+	move := func(id string, to DockZone) {
+		*follow = id
+		for z := range layout.Zones {
+			layout.Zones[z] = slices.DeleteFunc(slices.Clone(layout.Zones[z]), func(s string) bool { return s == id })
+		}
+		layout.Zones[to] = append(layout.Zones[to], id)
+		layout.Active[to] = id
+		changed = true
+		slog.Debug("mujica: dock_panel docked", "panel", id, "zone", to)
+	}
+	dragging := false
+	root.Children(func() {
+		ui.Column(c).Fill().Children(func() {
+			ui.Row(c).Grow(1).MinHeight(0).AlignItems(ui.Stretch).Children(func() {
+				for _, z := range []DockZone{DockLeft, DockCenter, DockRight} {
+					if dockPanelZone(c, k, u, layout, byID, z, disabled, move, &changed, follow) {
+						dragging = true
+					}
+				}
+			})
+			if dockPanelZone(c, k, u, layout, byID, DockBottom, disabled, move, &changed, follow) {
+				dragging = true
+			}
+		})
+		// Edges stay one frame after the drag, when the drop arrives.
+		was := ui.Local(root, "dock_panel.drag", func() bool { return false })
+		if (dragging || *was) && !disabled {
+			dockPanelEdges(c, k, u, move)
+		}
+		*was = dragging
+	})
+	return ChoiceResult{root, changed}
+}
+
+// dockPanelZone builds zone z's tabs and shown panel; it reports a tab of it being dragged.
+func dockPanelZone(c *ui.Context, k theme.Tokens, u float32, layout *DockLayout, byID map[string]DockItem, z DockZone, disabled bool, move func(string, DockZone), changed *bool, follow *string) bool {
+	ids := layout.Zones[z]
+	if len(ids) == 0 {
+		return false
+	}
+	box := ui.Column(c).Key(z).MinWidth(0).MinHeight(0).Background(k.Surface).Clip().Role(ui.RoleGroup).
+		Label(msg(c, fmt.Sprintf("dock_panel.zone%d", z)))
+	switch z {
+	case DockLeft, DockRight:
+		box.Width(220).Shrink(0).Border(theme.BorderWidth, k.Border)
+	case DockBottom:
+		box.Height(160).Shrink(0).Border(theme.BorderWidth, k.Border)
+	default:
+		box.Grow(1)
+	}
+	if d, ok := ui.DragOver[dockPanelDrag](box); ok && !slices.Contains(ids, d.id) {
+		box.Border(2, k.AccentText)
+	}
+	if d, ok := ui.Drop[dockPanelDrag](box); ok && !disabled {
+		move(d.id, z)
+	}
+	dragging := false
+	box.Children(func() {
+		at := slices.Index(ids, layout.Active[z])
+		base := ui.TabsBase(c, &at, len(ids))
+		base.List.Gap(u).Padding(theme.FocusGap+theme.FocusWidth, u*2, 0, u*2).Children(func() {
+			for i, id := range ids {
+				tab := base.Tab(i).Drag(dockPanelDrag{id})
+				tabsStyle(c, tab, Tab{Label: byID[id].Title}, i == at, false)
+				tab.Description(msg(c, "dock_panel.hint"))
+				if *follow == id {
+					tab.Focus()
+					*follow = ""
+				}
+				dragging = dragging || tab.Dragging()
+				for key, to := range map[ui.Key]DockZone{ui.KeyLeft: DockLeft, ui.KeyRight: DockRight, ui.KeyDown: DockBottom, ui.KeyUp: DockCenter} {
+					if tab.Shortcut(ui.Shift|ui.Alt, key) && !disabled && to != z {
+						move(id, to)
+					}
+				}
+			}
+		})
+		if base.List.Changed() && !disabled && ids[at] != layout.Active[z] {
+			layout.Active[z], *changed = ids[at], true
+		}
+		ui.Box(c).FillWidth().Height(theme.BorderWidth).Background(k.Border).Role(ui.RoleNone)
+		ui.Scroll(c).Grow(1).MinHeight(0).Padding(u * 3).Children(byID[layout.Active[z]].Build)
+	})
+	return dragging
+}
+
+// dockPanelEdges shows drop strips on the four edges while a tab is dragged.
+func dockPanelEdges(c *ui.Context, k theme.Tokens, u float32, move func(string, DockZone)) {
+	for _, z := range []DockZone{DockLeft, DockRight, DockBottom, DockCenter} {
+		e := ui.Box(c).Key(fmt.Sprint("edge", z)).Absolute().Role(ui.RoleNone)
+		switch z {
+		case DockLeft:
+			e.Left(0).Top(0).Bottom(0).Width(12 * u)
+		case DockRight:
+			e.Right(0).Top(0).Bottom(0).Width(12 * u)
+		case DockBottom:
+			e.Left(12 * u).Right(12 * u).Bottom(0).Height(10 * u)
+		default:
+			e.Left(0).Right(0).Top(0).Height(4 * u)
+		}
+		_, over := ui.DragOver[dockPanelDrag](e)
+		if over {
+			e.Background(k.Selection).Border(2, k.AccentText)
+		}
+		if d, ok := ui.Drop[dockPanelDrag](e); ok {
+			move(d.id, z)
+		}
+	}
+}
diff --git a/dock_panel_test.go b/dock_panel_test.go
new file mode 100644
index 0000000..20b5aa0
--- /dev/null
+++ b/dock_panel_test.go
@@ -0,0 +1,102 @@
+package mujica
+
+import (
+	"slices"
+	"testing"
+
+	"github.com/egoist/mygo/ui"
+)
+
+func dockItems(c *ui.Context) []DockItem {
+	var out []DockItem
+	for _, id := range []string{"files", "editor", "terminal"} {
+		out = append(out, DockItem{ID: id, Title: "Panel " + id, Build: func() { ui.Text(c, "Body of "+id) }})
+	}
+	return out
+}
+
+func dockTester(l *DockLayout, dis *bool, n *int) *ui.Tester {
+	return ui.NewTester(func(c *ui.Context) {
+		Use(c, Settings{})
+		r := DockPanel(c, l, dockItems(c), DockPanelOptions{Disabled: *dis})
+		r.Element.Size(800, 500)
+		if r.Changed() {
+			*n++
+		}
+	}, 820, 520)
+}
+
+func TestDockPanelTabsAndKeyboardDock(t *testing.T) {
+	var l DockLayout
+	dis, n := false, 0
+	tt := dockTester(&l, &dis, &n)
+	if !slices.Equal(l.Zones[DockCenter], []string{"files", "editor", "terminal"}) || l.Active[DockCenter] != "files" || !tt.HasText("Body of files") {
+		t.Fatalf("default layout %+v", l)
+	}
+	if err := tt.Click("Panel editor"); err != nil {
+		t.Fatal(err)
+	}
+	if l.Active[DockCenter] != "editor" || !tt.HasText("Body of editor") {
+		t.Fatalf("tab click: %+v", l)
+	}
+	tt.Key(ui.Shift|ui.Alt, ui.KeyLeft)
+	if !slices.Equal(l.Zones[DockLeft], []string{"editor"}) || slices.Contains(l.Zones[DockCenter], "editor") {
+		t.Fatalf("Shift+Alt+Left: %+v", l)
+	}
+	if _, ok := tt.Find("Left dock"); !ok {
+		t.Fatal("left zone not shown")
+	}
+	tt.Key(ui.Shift|ui.Alt, ui.KeyUp)
+	if len(l.Zones[DockLeft]) != 0 || l.Active[DockCenter] != "editor" {
+		t.Fatalf("back to center: %+v", l)
+	}
+	before := n
+	dis = true
+	tt.Frame()
+	tt.Key(ui.Shift|ui.Alt, ui.KeyDown)
+	if len(l.Zones[DockBottom]) != 0 || n != before {
+		t.Fatalf("disabled docked: %+v", l)
+	}
+}
+
+func TestDockPanelDragToEdge(t *testing.T) {
+	var l DockLayout
+	dis, n := false, 0
+	tt := dockTester(&l, &dis, &n)
+	r, _ := tt.Find("Panel terminal")
+	x, y := r.X+r.W/2, r.Y+r.H/2
+	tt.Press(x, y)
+	for _, px := range []float32{x + 10, x + 200, 600, 790} {
+		tt.Move(px, 250)
+	}
+	tt.Release(790, 250)
+	tt.Frame()
+	if !slices.Equal(l.Zones[DockRight], []string{"terminal"}) || n == 0 {
+		t.Fatalf("drag to the right edge: %+v", l)
+	}
+}
+
+func TestDockPanelRejects(t *testing.T) {
+	for name, l := range map[string]DockLayout{
+		"unknown":  {Zones: [4][]string{{"nope"}}},
+		"repeated": {Zones: [4][]string{{"files"}, {"files"}}},
+	} {
+		func() {
+			defer func() {
+				if recover() == nil {
+					t.Errorf("%s: no panic", name)
+				}
+			}()
+			ui.NewTester(func(c *ui.Context) { Use(c, Settings{}); DockPanel(c, &l, dockItems(c), DockPanelOptions{}) }, 300, 200)
+		}()
+	}
+}
+
+func TestDockPanelSnapshot(t *testing.T) {
+	l := DockLayout{Zones: [4][]string{{"editor"}, {"files"}, nil, {"terminal"}}}
+	snapshot(t, "dock_panel", 640, 360, func(c *ui.Context) {
+		ui.Column(c).Padding(12).Children(func() {
+			DockPanel(c, &l, dockItems(c), DockPanelOptions{}).Element.Size(616, 336)
+		})
+	})
+}
diff --git a/messages_essentials.go b/messages_essentials.go
index 618816a..5c9e9d2 100644
--- a/messages_essentials.go
+++ b/messages_essentials.go
@@ -30,6 +30,12 @@ func init() {
 
 		"resizable_panel_group.divider": {"Resize %s and %s", "调整 %s 与 %s 的大小"},
 
+		"dock_panel.zone0": {"Center dock", "中央停靠区"},
+		"dock_panel.zone1": {"Left dock", "左侧停靠区"},
+		"dock_panel.zone2": {"Right dock", "右侧停靠区"},
+		"dock_panel.zone3": {"Bottom dock", "底部停靠区"},
+		"dock_panel.hint":  {"Drag to an edge, or Shift+Alt+arrow, to dock", "拖到边缘，或按 Shift+Alt+方向键停靠"},
+
 		"qr_code.label":    {"QR code", "二维码"},
 		"qr_code.too_long": {"Text too long for a QR code", "文字过长，无法生成二维码"},
 	})
diff --git a/testdata/snapshots/darwin/dock_panel-dark.png b/testdata/snapshots/darwin/dock_panel-dark.png
new file mode 100644
index 0000000..cf54f97
Binary files /dev/null and b/testdata/snapshots/darwin/dock_panel-dark.png differ
diff --git a/testdata/snapshots/darwin/dock_panel-light.png b/testdata/snapshots/darwin/dock_panel-light.png
new file mode 100644
index 0000000..0cab0c0
Binary files /dev/null and b/testdata/snapshots/darwin/dock_panel-light.png differ