diff --git a/src/ClaudeDo.Ui/ViewModels/Modals/WorktreesOverviewModalViewModel.cs b/src/ClaudeDo.Ui/ViewModels/Modals/WorktreesOverviewModalViewModel.cs
index 9a1a930..f6c8f42 100644
--- a/src/ClaudeDo.Ui/ViewModels/Modals/WorktreesOverviewModalViewModel.cs
+++ b/src/ClaudeDo.Ui/ViewModels/Modals/WorktreesOverviewModalViewModel.cs
@@ -69,9 +69,18 @@ public sealed partial class WorktreesOverviewModalViewModel : ViewModelBase
     [ObservableProperty] private bool _isBusy;
     [ObservableProperty] private string? _statusMessage;
     [ObservableProperty] private WorktreeOverviewRowViewModel? _selectedRow;
+    [ObservableProperty] private string? _selectedTarget;
+    [ObservableProperty] private int _selectedCount;
+    [ObservableProperty] private bool _isMerging;
+    [ObservableProperty] private string? _batchProgress;
 
     public ObservableCollection<WorktreeOverviewRowViewModel> Rows { get; } = new();
     public ObservableCollection<WorktreesGroupViewModel> Groups { get; } = new();
+    public ObservableCollection<string> MergeTargets { get; } = new();
+    public ObservableCollection<WorktreeOverviewRowViewModel> ConflictRows { get; } = new();
+
+    /// Inert seam wired by the integrator to Layer C's resolver at merge time. (taskId, targetBranch)
+    public Func<string, string, Task>? RequestConflictResolution { get; set; }
 
     public Action? CloseAction { get; set; }
     public Action<WorktreeModalViewModel>? ShowDiffAction { get; set; }
@@ -265,4 +274,68 @@ public sealed partial class WorktreesOverviewModalViewModel : ViewModelBase
         Path = d.Path, BranchName = d.BranchName, BaseCommit = d.BaseCommit, State = d.State,
         DiffStat = d.DiffStat, CreatedAt = d.CreatedAt, PathExistsOnDisk = d.PathExistsOnDisk,
     };
+
+    public IEnumerable<WorktreeOverviewRowViewModel> AllRows =>
+        IsGlobal ? Groups.SelectMany(g => g.Rows) : Rows;
+
+    public async Task MergeSelectedAsync(
+        Func<string, string, bool, string, Task<MergeResultDto>> mergeFn,
+        CancellationToken ct = default)
+    {
+        var target = SelectedTarget;
+        if (string.IsNullOrWhiteSpace(target)) return;
+
+        var selected = AllRows.Where(r => r.IsChecked && r.IsActive).ToList();
+        if (selected.Count == 0) return;
+
+        IsMerging = true;
+        ConflictRows.Clear();
+        var done = 0;
+        try
+        {
+            foreach (var row in selected)
+            {
+                ct.ThrowIfCancellationRequested();
+                row.MergeOutcome = BatchMergeOutcome.Merging;
+                BatchProgress = Loc.T("vm.worktreesOverview.batchProgress", ++done, selected.Count);
+
+                MergeResultDto result;
+                try
+                {
+                    result = await mergeFn(row.TaskId, target!, false,
+                        Loc.T("vm.merge.commitMessage", row.TaskTitle));
+                }
+                catch
+                {
+                    row.MergeOutcome = BatchMergeOutcome.Failed;
+                    continue;
+                }
+
+                switch (result.Status)
+                {
+                    case "merged":
+                        row.MergeOutcome = BatchMergeOutcome.Merged;
+                        row.State = WorktreeState.Merged;
+                        row.IsChecked = false;
+                        break;
+                    case "conflict":
+                        row.MergeOutcome = BatchMergeOutcome.Conflict;
+                        ConflictRows.Add(row);
+                        break;
+                    case "blocked":
+                        row.MergeOutcome = BatchMergeOutcome.Blocked;
+                        break;
+                    default:
+                        row.MergeOutcome = BatchMergeOutcome.Failed;
+                        break;
+                }
+            }
+            BatchProgress = Loc.T("vm.worktreesOverview.batchDone",
+                selected.Count(r => r.MergeOutcome == BatchMergeOutcome.Merged), ConflictRows.Count);
+        }
+        finally
+        {
+            IsMerging = false;
+        }
+    }
 }
diff --git a/tests/ClaudeDo.Ui.Tests/ViewModels/WorktreesOverviewBatchMergeTests.cs b/tests/ClaudeDo.Ui.Tests/ViewModels/WorktreesOverviewBatchMergeTests.cs
index 4db056d..fda13bc 100644
--- a/tests/ClaudeDo.Ui.Tests/ViewModels/WorktreesOverviewBatchMergeTests.cs
+++ b/tests/ClaudeDo.Ui.Tests/ViewModels/WorktreesOverviewBatchMergeTests.cs
@@ -1,4 +1,5 @@
 using ClaudeDo.Data.Models;
+using ClaudeDo.Ui.Services;
 using ClaudeDo.Ui.ViewModels.Modals;
 using TaskStatus = ClaudeDo.Data.Models.TaskStatus;
 using Xunit;
@@ -28,4 +29,89 @@ public class WorktreesOverviewBatchMergeTests
         row.MergeOutcome = BatchMergeOutcome.Merged;
         Assert.False(row.IsConflict);
     }
+
+    private static WorktreesOverviewModalViewModel NewVm() =>
+        new(new ClaudeDo.Ui.Services.WorkerClient("http://127.0.0.1:1/hub"), () => null!);
+
+    private static MergeResultDto Merged() => new("merged", System.Array.Empty<string>(), null);
+    private static MergeResultDto Conflict() => new("conflict", new[] { "f.cs" }, null);
+    private static MergeResultDto Blocked() => new("blocked", System.Array.Empty<string>(), "blocked");
+
+    [Fact]
+    public async System.Threading.Tasks.Task MergeSelected_only_processes_checked_active_rows()
+    {
+        var vm = NewVm();
+        var a = ActiveRow("a"); a.IsChecked = true;
+        var b = ActiveRow("b"); b.IsChecked = false;
+        var c = ActiveRow("c"); c.IsChecked = true; c.State = WorktreeState.Merged;
+        vm.Rows.Add(a); vm.Rows.Add(b); vm.Rows.Add(c);
+        vm.SelectedTarget = "main";
+
+        var seen = new System.Collections.Generic.List<string>();
+        await vm.MergeSelectedAsync((id, target, remove, msg) =>
+        {
+            seen.Add(id);
+            Assert.Equal("main", target);
+            Assert.False(remove);
+            return System.Threading.Tasks.Task.FromResult(Merged());
+        });
+
+        Assert.Equal(new[] { "a" }, seen);
+        Assert.Equal(BatchMergeOutcome.Merged, a.MergeOutcome);
+        Assert.False(a.IsChecked);
+    }
+
+    [Fact]
+    public async System.Threading.Tasks.Task MergeSelected_continues_past_conflict_and_collects_it()
+    {
+        var vm = NewVm();
+        var a = ActiveRow("a"); a.IsChecked = true;
+        var b = ActiveRow("b"); b.IsChecked = true;
+        var c = ActiveRow("c"); c.IsChecked = true;
+        vm.Rows.Add(a); vm.Rows.Add(b); vm.Rows.Add(c);
+        vm.SelectedTarget = "main";
+
+        await vm.MergeSelectedAsync((id, target, remove, msg) =>
+            System.Threading.Tasks.Task.FromResult(id == "b" ? Conflict() : Merged()));
+
+        Assert.Equal(BatchMergeOutcome.Merged, a.MergeOutcome);
+        Assert.Equal(BatchMergeOutcome.Conflict, b.MergeOutcome);
+        Assert.Equal(BatchMergeOutcome.Merged, c.MergeOutcome);
+        Assert.Contains(b, vm.ConflictRows);
+        Assert.Single(vm.ConflictRows);
+    }
+
+    [Fact]
+    public async System.Threading.Tasks.Task MergeSelected_maps_blocked_and_exception_to_failure_outcomes()
+    {
+        var vm = NewVm();
+        var a = ActiveRow("a"); a.IsChecked = true;
+        var b = ActiveRow("b"); b.IsChecked = true;
+        vm.Rows.Add(a); vm.Rows.Add(b);
+        vm.SelectedTarget = "main";
+
+        await vm.MergeSelectedAsync((id, target, remove, msg) => id == "a"
+            ? System.Threading.Tasks.Task.FromResult(Blocked())
+            : throw new System.InvalidOperationException("boom"));
+
+        Assert.Equal(BatchMergeOutcome.Blocked, a.MergeOutcome);
+        Assert.Equal(BatchMergeOutcome.Failed, b.MergeOutcome);
+        Assert.Empty(vm.ConflictRows);
+        Assert.False(vm.IsMerging);
+    }
+
+    [Fact]
+    public async System.Threading.Tasks.Task MergeSelected_noop_when_no_target()
+    {
+        var vm = NewVm();
+        var a = ActiveRow("a"); a.IsChecked = true;
+        vm.Rows.Add(a);
+        vm.SelectedTarget = null;
+
+        var called = false;
+        await vm.MergeSelectedAsync((id, t, r, m) => { called = true; return System.Threading.Tasks.Task.FromResult(Merged()); });
+
+        Assert.False(called);
+        Assert.Equal(BatchMergeOutcome.None, a.MergeOutcome);
+    }
 }