diff --git a/src/text_editor/layout.cpp b/src/text_editor/layout.cpp
index 1648e9d..52faed9 100644
--- a/src/text_editor/layout.cpp
+++ b/src/text_editor/layout.cpp
@@ -20,7 +20,8 @@ struct HistoryEntry {
 };
 
 struct History {
-    Array<HistoryEntry> entries;
+    Array<HistoryEntry> undo_stack;
+    Array<HistoryEntry> redo_stack;
     int                 debug_edit_phase;
 };
 
@@ -287,14 +288,78 @@ void MergeCursors(Window *window) {
             new_cursors.add(it);
         }
     }
+    Assert(new_cursors.len <= window->cursors.len);
     window->cursors.dealloc();
     window->cursors = new_cursors;
 }
 
-void UndoEdit(Window *window) {
-    if (window->history.entries.len <= 0) return;
+void SaveHistoryBeforeMergeCursor(Window *window, Array<HistoryEntry> *stack) {
+    HistoryEntry *entry         = stack->alloc();
+    Allocator     sys_allocator = GetSystemAllocator();
+    entry->cursors              = window->cursors.tight_copy(sys_allocator);
+}
 
-    HistoryEntry entry = window->history.entries.pop();
+void SaveHistoryBeforeApplyEdits(Window *window, Array<HistoryEntry> *stack, Array<Edit> edits) {
+    HistoryEntry *entry         = stack->last();
+    Allocator     sys_allocator = GetSystemAllocator();
+    entry->edits                = edits.tight_copy(sys_allocator);
+
+    // Make reverse edits
+    For(entry->edits) {
+        Range  new_range = {it.range.min, it.range.min + it.string.len};
+        String string    = GetString(window->buffer, it.range);
+        it.string        = Copy(sys_allocator, string);
+        it.range         = new_range;
+    }
+
+    Array<Edit> temp_edits = entry->edits.tight_copy(sys_allocator);
+    defer { temp_edits.dealloc(); };
+
+    // Fix reverse edits
+    ForItem(edit, edits) {
+        int64_t remove_size = GetRangeSize(edit.range);
+        int64_t insert_size = edit.string.len;
+        int64_t offset      = insert_size - remove_size;
+
+        for (int64_t i = 0; i < entry->edits.len; i += 1) {
+            Edit &new_edit = entry->edits.data[i];
+            Edit &old_edit = temp_edits.data[i];
+            if (old_edit.range.min > edit.range.min) {
+                new_edit.range.min += offset;
+                new_edit.range.max += offset;
+            }
+        }
+    }
+}
+
+void RedoEdit(Window *window) {
+    if (window->history.redo_stack.len <= 0) return;
+
+    HistoryEntry entry = window->history.redo_stack.pop();
+
+    SaveHistoryBeforeMergeCursor(window, &window->history.undo_stack);
+    SaveHistoryBeforeApplyEdits(window, &window->history.undo_stack, entry.edits);
+    _ApplyEdits(&window->buffer, entry.edits);
+
+    window->cursors.dealloc();
+    window->cursors = entry.cursors;
+
+    Allocator sys_allocator = GetSystemAllocator();
+    For(entry.edits) Dealloc(sys_allocator, &it.string.data);
+    entry.edits.dealloc();
+
+    // Generate layout
+    Clear(&window->layout_arena);
+    window->layout = CalculateLayout(&window->layout_arena, window->buffer, window->font, window->font_size, window->font_spacing);
+}
+
+void UndoEdit(Window *window) {
+    if (window->history.undo_stack.len <= 0) return;
+
+    HistoryEntry entry = window->history.undo_stack.pop();
+
+    SaveHistoryBeforeMergeCursor(window, &window->history.redo_stack);
+    SaveHistoryBeforeApplyEdits(window, &window->history.redo_stack, entry.edits);
     _ApplyEdits(&window->buffer, entry.edits);
 
     window->cursors.dealloc();
@@ -312,55 +377,21 @@ void UndoEdit(Window *window) {
 void BeforeEdit(Window *window) {
     Assert(window->history.debug_edit_phase == 0);
     window->history.debug_edit_phase += 1;
-
-    {
-        History      &h             = window->history;
-        HistoryEntry *entry         = h.entries.alloc();
-        Allocator     sys_allocator = GetSystemAllocator();
-        Assert(window->cursors.len);
-        entry->cursors = window->cursors.tight_copy(sys_allocator);
+    Assert(window->cursors.len);
+    SaveHistoryBeforeMergeCursor(window, &window->history.undo_stack);
+    For(window->history.redo_stack) {
+        it.cursors.dealloc();
+        ForItem(edit, it.edits) Dealloc(it.edits.allocator, &edit.string.data);
+        it.edits.dealloc();
     }
-
+    window->history.redo_stack.dealloc();
     MergeCursors(window);
 }
 
 void ApplyEdits(Window *window, Array<Edit> edits) {
     Assert(window->history.debug_edit_phase == 1);
     window->history.debug_edit_phase += 1;
-
-    {
-        HistoryEntry *entry         = window->history.entries.last();
-        Allocator     sys_allocator = GetSystemAllocator();
-        entry->edits                = edits.tight_copy(sys_allocator);
-
-        // Make reverse edits
-        For(entry->edits) {
-            Range  new_range = {it.range.min, it.range.min + it.string.len};
-            String string    = GetString(window->buffer, it.range);
-            it.string        = Copy(sys_allocator, string);
-            it.range         = new_range;
-        }
-
-        Array<Edit> temp_edits = entry->edits.tight_copy(sys_allocator);
-        defer { temp_edits.dealloc(); };
-
-        // Fix reverse edits
-        ForItem(edit, edits) {
-            int64_t remove_size = GetRangeSize(edit.range);
-            int64_t insert_size = edit.string.len;
-            int64_t offset      = insert_size - remove_size;
-
-            for (int64_t i = 0; i < entry->edits.len; i += 1) {
-                Edit &new_edit = entry->edits.data[i];
-                Edit &old_edit = temp_edits.data[i];
-                if (old_edit.range.min > edit.range.min) {
-                    new_edit.range.min += offset;
-                    new_edit.range.max += offset;
-                }
-            }
-        }
-    }
-
+    SaveHistoryBeforeApplyEdits(window, &window->history.undo_stack, edits);
     _ApplyEdits(&window->buffer, edits);
 }
 
@@ -368,7 +399,7 @@ void AfterEdit(Window *window, Array<Edit> edits) {
     Assert(window->history.debug_edit_phase == 2);
     window->history.debug_edit_phase -= 2;
 
-    HistoryEntry *entry = window->history.entries.last();
+    HistoryEntry *entry = window->history.undo_stack.last();
     Assert(entry->cursors.len);
     Assert(entry->edits.len);
 
diff --git a/src/text_editor/main.cpp b/src/text_editor/main.cpp
index f779026..f3ef322 100644
--- a/src/text_editor/main.cpp
+++ b/src/text_editor/main.cpp
@@ -316,8 +316,14 @@ int main() {
                 AfterEdit(focused_window, edits);
             }
 
-            if (IsKeyDown(KEY_LEFT_CONTROL) && (IsKeyPressed(KEY_Z) || IsKeyPressedRepeat(KEY_Z))) {
-                UndoEdit(focused_window);
+            if ((IsKeyPressed(KEY_Z) || IsKeyPressedRepeat(KEY_Z))) {
+                if (IsKeyDown(KEY_LEFT_CONTROL)) {
+                    if (IsKeyDown(KEY_LEFT_SHIFT)) {
+                        RedoEdit(focused_window);
+                    } else {
+                        UndoEdit(focused_window);
+                    }
+                }
             }
 
             if (IsKeyPressed(KEY_DELETE) || IsKeyPressedRepeat(KEY_DELETE)) {