diff --git a/docs/plan/NewEditor_PortBoundaryRefactorPlan_2026-04-23.md b/docs/plan/NewEditor_PortBoundaryRefactorPlan_2026-04-23.md
new file mode 100644
index 00000000..c9f124ae
--- /dev/null
+++ b/docs/plan/NewEditor_PortBoundaryRefactorPlan_2026-04-23.md
@@ -0,0 +1,176 @@
+# NewEditor Port Boundary Refactor Plan
+
+Date: 2026-04-23
+Status: In Progress
+
+## 1. Objective
+
+Refactor `new_editor` so that external boundaries are modeled explicitly instead of being mixed into a single `app/Ports` bucket.
+
+This plan targets three concrete issues:
+
+1. `SystemInteractionPort` is a platform/system boundary.
+2. `TexturePort` and `ViewportRenderPort` are rendering host boundaries.
+3. `ShaderResourceDescriptorAllocatorPort` is not a real application boundary because it leaks `d3d12.h` types directly into the interface.
+
+The goal is to make the directory structure match the actual architecture, reduce "add another port" cargo cult growth, and make later editor features cheaper to extend.
+
+## 2. Current Problems
+
+### 2.1 Mixed abstraction levels
+
+`app/Ports` currently mixes:
+
+1. operating-system integration
+2. rendering-host integration
+3. backend-internal D3D12 helpers
+
+These are not the same architectural seam and should not share one bucket.
+
+### 2.2 The word "Port" is being used too broadly
+
+The current structure encourages a bad rule:
+
+"If something crosses a layer, add a port."
+
+That is not the intended use of ports. A port should exist only for a real boundary contract, not for every data handoff or helper collaboration.
+
+### 2.3 Fake abstraction in D3D12 descriptor allocation
+
+`ShaderResourceDescriptorAllocatorPort` exposes:
+
+1. `D3D12_CPU_DESCRIPTOR_HANDLE`
+2. `D3D12_GPU_DESCRIPTOR_HANDLE`
+3. `UINT`
+4. direct D3D12 header dependency
+
+That makes it a D3D12-specific helper wearing an interface costume. It should be concrete backend code unless there is a proven need for a cross-backend contract.
+
+## 3. Target End State
+
+After the refactor:
+
+1. system-facing services live in a system-oriented location and namespace
+2. rendering host contracts live under rendering host boundaries
+3. D3D12-only helpers stay D3D12-local unless a backend-agnostic contract is justified
+4. new features do not add interfaces by default; they only add one when a real host boundary appears
+
+## 4. Boundary Rules
+
+Use a boundary interface only when all of the following are true:
+
+1. the caller depends on an external capability
+2. dependency inversion is useful at the application boundary
+3. the contract can be expressed without leaking backend-only details
+4. there is a realistic need for substitution, testing, or multiple implementations
+
+Do not add a boundary interface for:
+
+1. feature-to-feature communication
+2. panel-to-runtime state transfer
+3. helpers inside one rendering backend
+4. temporary include avoidance
+
+## 5. Execution Phases
+
+### Phase A. Split the `app/Ports` bucket by responsibility
+
+Create explicit homes for:
+
+1. system interaction service
+2. rendering host contracts
+
+Then move call sites to the new locations and names.
+
+### Phase B. Remove the fake D3D12 port
+
+Delete `ShaderResourceDescriptorAllocatorPort` and make the descriptor allocator a concrete D3D12 helper again.
+
+### Phase C. Clean up forwarding and naming
+
+Replace `Ports::...` references with names that explain the real role:
+
+1. `System::SystemInteractionService`
+2. `Rendering::Host::UiTextureHost`
+3. `Rendering::Host::ViewportRenderHost`
+
+### Phase D. Validate and harden
+
+1. ensure no remaining includes depend on `app/Ports`
+2. ensure the app still builds
+3. document the rule for future extension
+
+## 6. File Plan
+
+### New files
+
+1. `new_editor/app/System/SystemInteractionService.h`
+2. `new_editor/app/Rendering/Host/HostFwd.h`
+3. `new_editor/app/Rendering/Host/UiTextureHost.h`
+4. `new_editor/app/Rendering/Host/ViewportRenderHost.h`
+
+### Files expected to be updated
+
+1. `new_editor/app/Bootstrap/Application.h`
+2. `new_editor/app/Bootstrap/Application.cpp`
+3. `new_editor/app/Composition/EditorContext.h`
+4. `new_editor/app/Composition/EditorContext.cpp`
+5. `new_editor/app/Composition/EditorShellRuntime.h`
+6. `new_editor/app/Composition/EditorShellRuntime.cpp`
+7. `new_editor/app/Features/Project/ProjectPanel.h`
+8. `new_editor/app/Features/Project/ProjectPanel.cpp`
+9. `new_editor/app/Features/Scene/SceneViewportFeature.h`
+10. `new_editor/app/Features/Scene/SceneViewportFeature.cpp`
+11. `new_editor/app/Features/Scene/SceneViewportController.h`
+12. `new_editor/app/Features/Scene/SceneViewportController.cpp`
+13. `new_editor/app/Features/Scene/SceneViewportToolOverlay.h`
+14. `new_editor/app/Features/Scene/SceneViewportToolOverlay.cpp`
+15. `new_editor/app/Rendering/Assets/BuiltInIcons.h`
+16. `new_editor/app/Rendering/Assets/BuiltInIcons.cpp`
+17. `new_editor/app/Rendering/D3D12/D3D12UiTextureHost.h`
+18. `new_editor/app/Rendering/D3D12/D3D12WindowRenderer.h`
+19. `new_editor/app/Rendering/D3D12/D3D12ShaderResourceDescriptorAllocator.h`
+20. `new_editor/app/Rendering/Viewport/ViewportHostService.h`
+21. `new_editor/app/Rendering/Viewport/ViewportHostService.cpp`
+22. `new_editor/app/Rendering/Viewport/ViewportRenderTargets.h`
+23. `new_editor/app/Rendering/Viewport/ViewportRenderTargets.cpp`
+24. `new_editor/app/Support/EmbeddedPngLoader.h`
+25. `new_editor/app/Support/EmbeddedPngLoader.cpp`
+26. `new_editor/app/Platform/Win32/System/Win32SystemInteractionHost.h`
+27. `new_editor/app/Platform/Win32/Content/EditorWindowContentController.h`
+
+### Files expected to be retired
+
+1. `new_editor/app/Ports/SystemInteractionPort.h`
+2. `new_editor/app/Ports/TexturePort.h`
+3. `new_editor/app/Ports/ViewportRenderPort.h`
+4. `new_editor/app/Ports/PortFwd.h`
+5. `new_editor/app/Ports/ShaderResourceDescriptorAllocatorPort.h`
+
+## 7. First Execution Slice
+
+Execute the smallest high-value slice first:
+
+1. introduce the new system and rendering host interface headers
+2. switch call sites away from `Ports::`
+3. remove `ShaderResourceDescriptorAllocatorPort`
+4. leave behavior unchanged
+
+This keeps risk lower while immediately fixing the worst architectural confusion.
+
+## 8. Validation
+
+Minimum validation for this refactor:
+
+1. `rg "Ports::|Ports/" new_editor/app` returns no production references
+2. `ShaderResourceDescriptorAllocatorPort` no longer exists
+3. `XCUIEditorApp` compiles, or any build failure is isolated and reported precisely
+
+## 9. Completion Criteria
+
+This refactor is complete only when:
+
+1. `app/Ports` is no longer the active boundary bucket
+2. system and rendering host boundaries are visibly separated
+3. D3D12-only helpers are no longer presented as generic app ports
+4. future contributors can answer "where should a new boundary go?" without guessing
diff --git a/engine/include/XCEngine/Components/GameObject.h b/engine/include/XCEngine/Components/GameObject.h
index 5abd137f..b79f933f 100644
--- a/engine/include/XCEngine/Components/GameObject.h
+++ b/engine/include/XCEngine/Components/GameObject.h
@@ -189,6 +189,7 @@ public:
     GameObject* GetParent() const { return m_parent; }
     void SetParent(GameObject* parent);
     void SetParent(GameObject* parent, bool worldPositionStays);
+    void SetParent(GameObject* parent, size_t siblingIndex, bool worldPositionStays);
 
     size_t GetChildCount() const { return m_children.size(); }
     GameObject* GetChild(size_t index) const;
diff --git a/engine/src/Components/GameObject.cpp b/engine/src/Components/GameObject.cpp
index 18c5cf2e..64efd24f 100644
--- a/engine/src/Components/GameObject.cpp
+++ b/engine/src/Components/GameObject.cpp
@@ -114,6 +114,22 @@ void GameObject::SetParent(GameObject* parent, bool worldPositionStays) {
         return;
     }
 
+    SetParent(
+        parent,
+        parent != nullptr
+            ? parent->m_children.size()
+            : (m_scene != nullptr ? m_scene->m_rootGameObjects.size() : 0u),
+        worldPositionStays);
+}
+
+void GameObject::SetParent(
+    GameObject* parent,
+    size_t siblingIndex,
+    bool worldPositionStays) {
+    if (parent == this) {
+        return;
+    }
+
     const bool oldParentActiveInHierarchy = m_parent ? m_parent->IsActiveInHierarchy() : true;
     const bool wasActiveInHierarchy = oldParentActiveInHierarchy && m_activeSelf;
 
@@ -128,11 +144,16 @@ void GameObject::SetParent(GameObject* parent, bool worldPositionStays) {
     m_parent = parent;
 
     if (m_parent) {
-        m_parent->m_children.push_back(this);
+        auto& siblings = m_parent->m_children;
+        const size_t insertIndex = (std::min)(siblingIndex, siblings.size());
+        siblings.insert(siblings.begin() + static_cast<std::ptrdiff_t>(insertIndex), this);
     } else if (m_scene) {
         auto& roots = m_scene->m_rootGameObjects;
         if (std::find(roots.begin(), roots.end(), m_id) == roots.end()) {
-            roots.push_back(m_id);
+            const size_t insertIndex = (std::min)(siblingIndex, roots.size());
+            roots.insert(
+                roots.begin() + static_cast<std::ptrdiff_t>(insertIndex),
+                m_id);
         }
     }
 
diff --git a/new_editor/app/Features/Hierarchy/HierarchyPanel.cpp b/new_editor/app/Features/Hierarchy/HierarchyPanel.cpp
index 754ebf40..f4ffd13a 100644
--- a/new_editor/app/Features/Hierarchy/HierarchyPanel.cpp
+++ b/new_editor/app/Features/Hierarchy/HierarchyPanel.cpp
@@ -473,6 +473,28 @@ void HierarchyPanel::ProcessDragAndFrameEvents(
             return model.CanReparent(draggedItemId, targetItemId);
         }
 
+        bool CanInsertBeforeItem(
+            std::string_view draggedItemId,
+            std::string_view targetItemId) const {
+            if (draggedItemId.empty() ||
+                targetItemId.empty() ||
+                draggedItemId == targetItemId) {
+                return false;
+            }
+
+            const std::optional<std::string> targetParentId =
+                model.GetParentId(targetItemId);
+            return targetParentId.has_value()
+                ? model.CanReparent(draggedItemId, targetParentId.value())
+                : model.ContainsNode(draggedItemId);
+        }
+
+        bool CanInsertAfterItem(
+            std::string_view draggedItemId,
+            std::string_view targetItemId) const {
+            return CanInsertBeforeItem(draggedItemId, targetItemId);
+        }
+
         bool CanDropToRoot(std::string_view draggedItemId) const {
             return model.GetParentId(draggedItemId).has_value();
         }
@@ -484,6 +506,20 @@ void HierarchyPanel::ProcessDragAndFrameEvents(
                 sceneRuntime->ReparentGameObject(draggedItemId, targetItemId);
         }
 
+        bool CommitInsertBeforeItem(
+            std::string_view draggedItemId,
+            std::string_view targetItemId) {
+            return sceneRuntime != nullptr &&
+                sceneRuntime->MoveGameObjectBefore(draggedItemId, targetItemId);
+        }
+
+        bool CommitInsertAfterItem(
+            std::string_view draggedItemId,
+            std::string_view targetItemId) {
+            return sceneRuntime != nullptr &&
+                sceneRuntime->MoveGameObjectAfter(draggedItemId, targetItemId);
+        }
+
         bool CommitDropToRoot(std::string_view draggedItemId) {
             return sceneRuntime != nullptr &&
                 sceneRuntime->MoveGameObjectToRoot(draggedItemId);
@@ -705,7 +741,7 @@ void HierarchyPanel::Append(UIDrawList& drawList) const {
         m_treeFrame.layout,
         presentedItems,
         m_dragState.dragging && m_dragState.validDropTarget,
-        m_dragState.dropToRoot,
+        m_dragState.dropPlacement,
         m_dragState.dropTargetItemId,
         kDragPreviewColor,
         1.0f,
diff --git a/new_editor/app/Platform/Win32/BorderlessWindowChrome.cpp b/new_editor/app/Platform/Win32/Chrome/BorderlessWindowChrome.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/BorderlessWindowChrome.cpp
rename to new_editor/app/Platform/Win32/Chrome/BorderlessWindowChrome.cpp
diff --git a/new_editor/app/Platform/Win32/BorderlessWindowChrome.h b/new_editor/app/Platform/Win32/Chrome/BorderlessWindowChrome.h
similarity index 100%
rename from new_editor/app/Platform/Win32/BorderlessWindowChrome.h
rename to new_editor/app/Platform/Win32/Chrome/BorderlessWindowChrome.h
diff --git a/new_editor/app/Platform/Win32/BorderlessWindowFrame.cpp b/new_editor/app/Platform/Win32/Chrome/BorderlessWindowFrame.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/BorderlessWindowFrame.cpp
rename to new_editor/app/Platform/Win32/Chrome/BorderlessWindowFrame.cpp
diff --git a/new_editor/app/Platform/Win32/BorderlessWindowFrame.h b/new_editor/app/Platform/Win32/Chrome/BorderlessWindowFrame.h
similarity index 100%
rename from new_editor/app/Platform/Win32/BorderlessWindowFrame.h
rename to new_editor/app/Platform/Win32/Chrome/BorderlessWindowFrame.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowChromeController.cpp b/new_editor/app/Platform/Win32/Chrome/EditorWindowChromeController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowChromeController.cpp
rename to new_editor/app/Platform/Win32/Chrome/EditorWindowChromeController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindowChromeController.h b/new_editor/app/Platform/Win32/Chrome/EditorWindowChromeController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowChromeController.h
rename to new_editor/app/Platform/Win32/Chrome/EditorWindowChromeController.h
diff --git a/new_editor/app/Platform/Win32/HostRuntimeState.h b/new_editor/app/Platform/Win32/Chrome/HostRuntimeState.h
similarity index 100%
rename from new_editor/app/Platform/Win32/HostRuntimeState.h
rename to new_editor/app/Platform/Win32/Chrome/HostRuntimeState.h
diff --git a/new_editor/app/Platform/Win32/EditorAddComponentUtilityWindowContentController.cpp b/new_editor/app/Platform/Win32/Content/EditorAddComponentUtilityWindowContentController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorAddComponentUtilityWindowContentController.cpp
rename to new_editor/app/Platform/Win32/Content/EditorAddComponentUtilityWindowContentController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorAddComponentUtilityWindowContentController.h b/new_editor/app/Platform/Win32/Content/EditorAddComponentUtilityWindowContentController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorAddComponentUtilityWindowContentController.h
rename to new_editor/app/Platform/Win32/Content/EditorAddComponentUtilityWindowContentController.h
diff --git a/new_editor/app/Platform/Win32/EditorColorPickerUtilityWindowContentController.cpp b/new_editor/app/Platform/Win32/Content/EditorColorPickerUtilityWindowContentController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorColorPickerUtilityWindowContentController.cpp
rename to new_editor/app/Platform/Win32/Content/EditorColorPickerUtilityWindowContentController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorColorPickerUtilityWindowContentController.h b/new_editor/app/Platform/Win32/Content/EditorColorPickerUtilityWindowContentController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorColorPickerUtilityWindowContentController.h
rename to new_editor/app/Platform/Win32/Content/EditorColorPickerUtilityWindowContentController.h
diff --git a/new_editor/app/Platform/Win32/EditorStandaloneUtilityWindowContentController.cpp b/new_editor/app/Platform/Win32/Content/EditorStandaloneUtilityWindowContentController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorStandaloneUtilityWindowContentController.cpp
rename to new_editor/app/Platform/Win32/Content/EditorStandaloneUtilityWindowContentController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorStandaloneUtilityWindowContentController.h b/new_editor/app/Platform/Win32/Content/EditorStandaloneUtilityWindowContentController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorStandaloneUtilityWindowContentController.h
rename to new_editor/app/Platform/Win32/Content/EditorStandaloneUtilityWindowContentController.h
diff --git a/new_editor/app/Platform/Win32/EditorUtilityWindowKind.h b/new_editor/app/Platform/Win32/Content/EditorUtilityWindowKind.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorUtilityWindowKind.h
rename to new_editor/app/Platform/Win32/Content/EditorUtilityWindowKind.h
diff --git a/new_editor/app/Platform/Win32/EditorUtilityWindowRegistry.cpp b/new_editor/app/Platform/Win32/Content/EditorUtilityWindowRegistry.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorUtilityWindowRegistry.cpp
rename to new_editor/app/Platform/Win32/Content/EditorUtilityWindowRegistry.cpp
diff --git a/new_editor/app/Platform/Win32/EditorUtilityWindowRegistry.h b/new_editor/app/Platform/Win32/Content/EditorUtilityWindowRegistry.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorUtilityWindowRegistry.h
rename to new_editor/app/Platform/Win32/Content/EditorUtilityWindowRegistry.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowContentController.h b/new_editor/app/Platform/Win32/Content/EditorWindowContentController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowContentController.h
rename to new_editor/app/Platform/Win32/Content/EditorWindowContentController.h
diff --git a/new_editor/app/Platform/Win32/EditorWorkspaceWindowContentController.cpp b/new_editor/app/Platform/Win32/Content/EditorWorkspaceWindowContentController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWorkspaceWindowContentController.cpp
rename to new_editor/app/Platform/Win32/Content/EditorWorkspaceWindowContentController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWorkspaceWindowContentController.h b/new_editor/app/Platform/Win32/Content/EditorWorkspaceWindowContentController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWorkspaceWindowContentController.h
rename to new_editor/app/Platform/Win32/Content/EditorWorkspaceWindowContentController.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowFrameDriver.cpp b/new_editor/app/Platform/Win32/Runtime/EditorWindowFrameDriver.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowFrameDriver.cpp
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowFrameDriver.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindowFrameDriver.h b/new_editor/app/Platform/Win32/Runtime/EditorWindowFrameDriver.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowFrameDriver.h
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowFrameDriver.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowFrameOrchestrator.cpp b/new_editor/app/Platform/Win32/Runtime/EditorWindowFrameOrchestrator.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowFrameOrchestrator.cpp
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowFrameOrchestrator.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindowFrameOrchestrator.h b/new_editor/app/Platform/Win32/Runtime/EditorWindowFrameOrchestrator.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowFrameOrchestrator.h
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowFrameOrchestrator.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowInputController.cpp b/new_editor/app/Platform/Win32/Runtime/EditorWindowInputController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowInputController.cpp
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowInputController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindowInputController.h b/new_editor/app/Platform/Win32/Runtime/EditorWindowInputController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowInputController.h
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowInputController.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowRuntimeController.cpp b/new_editor/app/Platform/Win32/Runtime/EditorWindowRuntimeController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowRuntimeController.cpp
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowRuntimeController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindowRuntimeController.h b/new_editor/app/Platform/Win32/Runtime/EditorWindowRuntimeController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowRuntimeController.h
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowRuntimeController.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowScreenshotController.cpp b/new_editor/app/Platform/Win32/Runtime/EditorWindowScreenshotController.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowScreenshotController.cpp
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowScreenshotController.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindowScreenshotController.h b/new_editor/app/Platform/Win32/Runtime/EditorWindowScreenshotController.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowScreenshotController.h
rename to new_editor/app/Platform/Win32/Runtime/EditorWindowScreenshotController.h
diff --git a/new_editor/app/Platform/Win32/InputModifierTracker.h b/new_editor/app/Platform/Win32/Runtime/InputModifierTracker.h
similarity index 100%
rename from new_editor/app/Platform/Win32/InputModifierTracker.h
rename to new_editor/app/Platform/Win32/Runtime/InputModifierTracker.h
diff --git a/new_editor/app/Platform/Win32/Win32SystemInteractionHost.cpp b/new_editor/app/Platform/Win32/System/Win32SystemInteractionHost.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/Win32SystemInteractionHost.cpp
rename to new_editor/app/Platform/Win32/System/Win32SystemInteractionHost.cpp
diff --git a/new_editor/app/Platform/Win32/Win32SystemInteractionHost.h b/new_editor/app/Platform/Win32/System/Win32SystemInteractionHost.h
similarity index 100%
rename from new_editor/app/Platform/Win32/Win32SystemInteractionHost.h
rename to new_editor/app/Platform/Win32/System/Win32SystemInteractionHost.h
diff --git a/new_editor/app/Platform/Win32/EditorFloatingWindowPlacement.cpp b/new_editor/app/Platform/Win32/Windowing/EditorFloatingWindowPlacement.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorFloatingWindowPlacement.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorFloatingWindowPlacement.cpp
diff --git a/new_editor/app/Platform/Win32/EditorFloatingWindowPlacement.h b/new_editor/app/Platform/Win32/Windowing/EditorFloatingWindowPlacement.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorFloatingWindowPlacement.h
rename to new_editor/app/Platform/Win32/Windowing/EditorFloatingWindowPlacement.h
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorUtilityWindowCoordinator.cpp b/new_editor/app/Platform/Win32/Windowing/EditorUtilityWindowCoordinator.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorUtilityWindowCoordinator.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorUtilityWindowCoordinator.cpp
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorUtilityWindowCoordinator.h b/new_editor/app/Platform/Win32/Windowing/EditorUtilityWindowCoordinator.h
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorUtilityWindowCoordinator.h
rename to new_editor/app/Platform/Win32/Windowing/EditorUtilityWindowCoordinator.h
diff --git a/new_editor/app/Platform/Win32/EditorWindow.cpp b/new_editor/app/Platform/Win32/Windowing/EditorWindow.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindow.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorWindow.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindow.h b/new_editor/app/Platform/Win32/Windowing/EditorWindow.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindow.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindow.h
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowHostRuntime.cpp b/new_editor/app/Platform/Win32/Windowing/EditorWindowHostRuntime.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowHostRuntime.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowHostRuntime.cpp
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowHostRuntime.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowHostRuntime.h
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowHostRuntime.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowHostRuntime.h
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowLifecycleCoordinator.cpp b/new_editor/app/Platform/Win32/Windowing/EditorWindowLifecycleCoordinator.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowLifecycleCoordinator.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowLifecycleCoordinator.cpp
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowLifecycleCoordinator.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowLifecycleCoordinator.h
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowLifecycleCoordinator.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowLifecycleCoordinator.h
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowManager.cpp b/new_editor/app/Platform/Win32/Windowing/EditorWindowManager.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowManager.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowManager.cpp
diff --git a/new_editor/app/Platform/Win32/EditorWindowManager.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowManager.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowManager.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowManager.h
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowMessageDispatcher.cpp b/new_editor/app/Platform/Win32/Windowing/EditorWindowMessageDispatcher.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowMessageDispatcher.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowMessageDispatcher.cpp
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowMessageDispatcher.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowMessageDispatcher.h
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowMessageDispatcher.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowMessageDispatcher.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowPointerCapture.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowPointerCapture.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowPointerCapture.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowPointerCapture.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowState.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowState.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowState.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowState.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowSupport.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowSupport.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowSupport.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowSupport.h
diff --git a/new_editor/app/Platform/Win32/EditorWindowTransferRequests.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowTransferRequests.h
similarity index 100%
rename from new_editor/app/Platform/Win32/EditorWindowTransferRequests.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowTransferRequests.h
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowWorkspaceCoordinator.cpp b/new_editor/app/Platform/Win32/Windowing/EditorWindowWorkspaceCoordinator.cpp
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowWorkspaceCoordinator.cpp
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowWorkspaceCoordinator.cpp
diff --git a/new_editor/app/Platform/Win32/WindowManager/EditorWindowWorkspaceCoordinator.h b/new_editor/app/Platform/Win32/Windowing/EditorWindowWorkspaceCoordinator.h
similarity index 100%
rename from new_editor/app/Platform/Win32/WindowManager/EditorWindowWorkspaceCoordinator.h
rename to new_editor/app/Platform/Win32/Windowing/EditorWindowWorkspaceCoordinator.h
diff --git a/new_editor/app/Scene/EditorSceneBridge.cpp b/new_editor/app/Scene/EditorSceneBridge.cpp
index 43a90f9a..409c5852 100644
--- a/new_editor/app/Scene/EditorSceneBridge.cpp
+++ b/new_editor/app/Scene/EditorSceneBridge.cpp
@@ -145,6 +145,79 @@ bool WouldCreateCycle(
     return false;
 }
 
+std::vector<GameObject*> ResolveSiblingSequence(
+    Scene& scene,
+    GameObject* parent) {
+    return parent != nullptr
+        ? parent->GetChildren()
+        : scene.GetRootGameObjects();
+}
+
+std::optional<std::size_t> FindSiblingIndex(
+    const std::vector<GameObject*>& siblings,
+    const GameObject* gameObject) {
+    if (gameObject == nullptr) {
+        return std::nullopt;
+    }
+
+    const auto it =
+        std::find(siblings.begin(), siblings.end(), gameObject);
+    if (it == siblings.end()) {
+        return std::nullopt;
+    }
+
+    return static_cast<std::size_t>(std::distance(siblings.begin(), it));
+}
+
+bool MoveGameObjectRelativeToTarget(
+    std::string_view itemId,
+    std::string_view targetItemId,
+    bool placeAfterTarget) {
+    Scene* scene = ResolvePrimaryScene();
+    GameObject* gameObject = FindEditorGameObject(itemId);
+    GameObject* target = FindEditorGameObject(targetItemId);
+    if (scene == nullptr ||
+        gameObject == nullptr ||
+        target == nullptr ||
+        gameObject == target) {
+        return false;
+    }
+
+    GameObject* targetParent = target->GetParent();
+    if (targetParent != nullptr &&
+        WouldCreateCycle(*gameObject, *targetParent)) {
+        return false;
+    }
+
+    const std::vector<GameObject*> siblings =
+        ResolveSiblingSequence(*scene, targetParent);
+    const std::optional<std::size_t> targetIndex =
+        FindSiblingIndex(siblings, target);
+    if (!targetIndex.has_value()) {
+        return false;
+    }
+
+    std::size_t finalIndex =
+        targetIndex.value() + (placeAfterTarget ? 1u : 0u);
+    if (gameObject->GetParent() == targetParent) {
+        const std::optional<std::size_t> sourceIndex =
+            FindSiblingIndex(siblings, gameObject);
+        if (sourceIndex.has_value()) {
+            if ((!placeAfterTarget && sourceIndex.value() < targetIndex.value()) ||
+                (placeAfterTarget && sourceIndex.value() <= targetIndex.value())) {
+                --finalIndex;
+            }
+
+            if (finalIndex == sourceIndex.value()) {
+                return false;
+            }
+        }
+    }
+
+    gameObject->SetParent(targetParent, finalIndex, true);
+    return true;
+}
+
 } // namespace
 
 EditorStartupSceneResult EnsureEditorStartupScene(
@@ -330,6 +403,18 @@ bool ReparentEditorGameObject(
     return true;
 }
 
+bool MoveEditorGameObjectBefore(
+    std::string_view itemId,
+    std::string_view targetItemId) {
+    return MoveGameObjectRelativeToTarget(itemId, targetItemId, false);
+}
+
+bool MoveEditorGameObjectAfter(
+    std::string_view itemId,
+    std::string_view targetItemId) {
+    return MoveGameObjectRelativeToTarget(itemId, targetItemId, true);
+}
+
 bool MoveEditorGameObjectToRoot(std::string_view itemId) {
     GameObject* gameObject = FindEditorGameObject(itemId);
     if (gameObject == nullptr || gameObject->GetParent() == nullptr) {
diff --git a/new_editor/app/Scene/EditorSceneBridge.h b/new_editor/app/Scene/EditorSceneBridge.h
index 215c5382..1c0f2bb3 100644
--- a/new_editor/app/Scene/EditorSceneBridge.h
+++ b/new_editor/app/Scene/EditorSceneBridge.h
@@ -39,6 +39,12 @@ std::string DuplicateEditorGameObject(std::string_view itemId);
 bool ReparentEditorGameObject(
     std::string_view itemId,
     std::string_view parentItemId);
+bool MoveEditorGameObjectBefore(
+    std::string_view itemId,
+    std::string_view targetItemId);
+bool MoveEditorGameObjectAfter(
+    std::string_view itemId,
+    std::string_view targetItemId);
 bool MoveEditorGameObjectToRoot(std::string_view itemId);
 
 } // namespace XCEngine::UI::Editor::App
diff --git a/new_editor/app/Scene/EditorSceneRuntime.cpp b/new_editor/app/Scene/EditorSceneRuntime.cpp
index f6085b74..3ebc3ca3 100644
--- a/new_editor/app/Scene/EditorSceneRuntime.cpp
+++ b/new_editor/app/Scene/EditorSceneRuntime.cpp
@@ -463,6 +463,32 @@ bool EditorSceneRuntime::ReparentGameObject(
     return reparented;
 }
 
+bool EditorSceneRuntime::MoveGameObjectBefore(
+    std::string_view itemId,
+    std::string_view targetItemId) {
+    ResetTransformEditHistory();
+    const bool moved =
+        MoveEditorGameObjectBefore(itemId, targetItemId);
+    if (moved) {
+        IncrementInspectorRevision();
+    }
+    RefreshScene();
+    return moved;
+}
+
+bool EditorSceneRuntime::MoveGameObjectAfter(
+    std::string_view itemId,
+    std::string_view targetItemId) {
+    ResetTransformEditHistory();
+    const bool moved =
+        MoveEditorGameObjectAfter(itemId, targetItemId);
+    if (moved) {
+        IncrementInspectorRevision();
+    }
+    RefreshScene();
+    return moved;
+}
+
 bool EditorSceneRuntime::MoveGameObjectToRoot(std::string_view itemId) {
     ResetTransformEditHistory();
     const bool moved = MoveEditorGameObjectToRoot(itemId);
diff --git a/new_editor/app/Scene/EditorSceneRuntime.h b/new_editor/app/Scene/EditorSceneRuntime.h
index ddd613ed..c72fd5be 100644
--- a/new_editor/app/Scene/EditorSceneRuntime.h
+++ b/new_editor/app/Scene/EditorSceneRuntime.h
@@ -93,6 +93,12 @@ public:
     bool ReparentGameObject(
         std::string_view itemId,
         std::string_view parentItemId);
+    bool MoveGameObjectBefore(
+        std::string_view itemId,
+        std::string_view targetItemId);
+    bool MoveGameObjectAfter(
+        std::string_view itemId,
+        std::string_view targetItemId);
     bool MoveGameObjectToRoot(std::string_view itemId);
     bool AddComponentToSelectedGameObject(std::string_view componentTypeName);
     bool CanRemoveSelectedComponent(std::string_view componentId) const;
diff --git a/new_editor/include/XCEditor/Collections/UIEditorTreeDragDrop.h b/new_editor/include/XCEditor/Collections/UIEditorTreeDragDrop.h
index a1e72cc0..60603cd3 100644
--- a/new_editor/include/XCEditor/Collections/UIEditorTreeDragDrop.h
+++ b/new_editor/include/XCEditor/Collections/UIEditorTreeDragDrop.h
@@ -5,6 +5,8 @@
 
 #include <XCEngine/UI/Types.h>
 
+#include <algorithm>
+#include <concepts>
 #include <string>
 #include <string_view>
 #include <vector>
@@ -18,9 +20,12 @@ using Widgets::HitTestUIEditorTreeView;
 using Widgets::UIEditorTreeViewHitTarget;
 using Widgets::UIEditorTreeViewHitTargetKind;
 using Widgets::UIEditorTreeViewInvalidIndex;
+using ::XCEngine::UI::Editor::UIEditorTreeViewDropPreviewPlacement;
 
 struct State : DragDropInteraction::State {
     bool dropToRoot = false;
+    UIEditorTreeViewDropPreviewPlacement dropPlacement =
+        UIEditorTreeViewDropPreviewPlacement::None;
 };
 
 struct ProcessResult : DragDropInteraction::ProcessResult {
@@ -42,6 +47,77 @@ inline bool ContainsPoint(const UIRect& rect, const UIPoint& point) {
         point.y <= rect.y + rect.height;
 }
 
+template <typename Callbacks>
+inline constexpr bool SupportsSiblingInsertion() {
+    return requires(
+        Callbacks& callbacks,
+        std::string_view draggedItemId,
+        std::string_view targetItemId) {
+        { callbacks.CanInsertBeforeItem(draggedItemId, targetItemId) } -> std::convertible_to<bool>;
+        { callbacks.CanInsertAfterItem(draggedItemId, targetItemId) } -> std::convertible_to<bool>;
+        { callbacks.CommitInsertBeforeItem(draggedItemId, targetItemId) } -> std::convertible_to<bool>;
+        { callbacks.CommitInsertAfterItem(draggedItemId, targetItemId) } -> std::convertible_to<bool>;
+    };
+}
+
+inline UIEditorTreeViewDropPreviewPlacement ResolveRowDropPlacement(
+    const Widgets::UIEditorTreeViewLayout& layout,
+    const UIEditorTreeViewHitTarget& hitTarget,
+    const UIPoint& point) {
+    if (hitTarget.visibleIndex >= layout.rowRects.size()) {
+        return UIEditorTreeViewDropPreviewPlacement::None;
+    }
+
+    const UIRect& rowRect = layout.rowRects[hitTarget.visibleIndex];
+    const float edgeBand =
+        (std::min)((std::max)(rowRect.height * 0.25f, 4.0f), 8.0f);
+    if (point.y <= rowRect.y + edgeBand) {
+        return UIEditorTreeViewDropPreviewPlacement::BeforeItem;
+    }
+    if (point.y >= rowRect.y + rowRect.height - edgeBand) {
+        return UIEditorTreeViewDropPreviewPlacement::AfterItem;
+    }
+
+    return UIEditorTreeViewDropPreviewPlacement::OnItem;
+}
+
+inline const Widgets::UIEditorTreeViewItem* ResolveGapInsertionItem(
+    const Widgets::UIEditorTreeViewLayout& layout,
+    const std::vector<Widgets::UIEditorTreeViewItem>& items,
+    const UIPoint& point,
+    UIEditorTreeViewDropPreviewPlacement& outPlacement) {
+    outPlacement = UIEditorTreeViewDropPreviewPlacement::None;
+    if (layout.rowRects.empty()) {
+        return nullptr;
+    }
+
+    if (point.y < layout.rowRects.front().y) {
+        outPlacement = UIEditorTreeViewDropPreviewPlacement::BeforeItem;
+        const std::size_t itemIndex = layout.visibleItemIndices.front();
+        return itemIndex < items.size() ? &items[itemIndex] : nullptr;
+    }
+
+    for (std::size_t visibleIndex = 0u; visibleIndex + 1u < layout.rowRects.size(); ++visibleIndex) {
+        const UIRect& currentRow = layout.rowRects[visibleIndex];
+        const UIRect& nextRow = layout.rowRects[visibleIndex + 1u];
+        if (point.y > currentRow.y + currentRow.height &&
+            point.y < nextRow.y) {
+            outPlacement = UIEditorTreeViewDropPreviewPlacement::BeforeItem;
+            const std::size_t itemIndex = layout.visibleItemIndices[visibleIndex + 1u];
+            return itemIndex < items.size() ? &items[itemIndex] : nullptr;
+        }
+    }
+
+    const UIRect& lastRow = layout.rowRects.back();
+    if (point.y > lastRow.y + lastRow.height) {
+        outPlacement = UIEditorTreeViewDropPreviewPlacement::AfterItem;
+        const std::size_t itemIndex = layout.visibleItemIndices.back();
+        return itemIndex < items.size() ? &items[itemIndex] : nullptr;
+    }
+
+    return nullptr;
+}
+
 inline const Widgets::UIEditorTreeViewItem* ResolveHitItem(
     const Widgets::UIEditorTreeViewLayout& layout,
     const std::vector<Widgets::UIEditorTreeViewItem>& items,
@@ -177,6 +253,7 @@ ProcessResult ProcessInputEvents(
         void ResetDropTarget(State& state) const {
             state.dropTargetItemId.clear();
             state.dropToRoot = false;
+            state.dropPlacement = UIEditorTreeViewDropPreviewPlacement::None;
             state.validDropTarget = false;
         }
 
@@ -190,14 +267,71 @@ ProcessResult ProcessInputEvents(
             if (hitItem != nullptr &&
                 (hitTarget.kind == UIEditorTreeViewHitTargetKind::Row ||
                  hitTarget.kind == UIEditorTreeViewHitTargetKind::Disclosure)) {
+                UIEditorTreeViewDropPreviewPlacement placement =
+                    UIEditorTreeViewDropPreviewPlacement::OnItem;
+                if constexpr (SupportsSiblingInsertion<Callbacks>()) {
+                    placement =
+                        hitTarget.kind == UIEditorTreeViewHitTargetKind::Disclosure
+                            ? UIEditorTreeViewDropPreviewPlacement::OnItem
+                            : ResolveRowDropPlacement(layout, hitTarget, point);
+                }
+
                 state.dropTargetItemId = hitItem->itemId;
-                state.validDropTarget =
-                    callbacks.CanDropOnItem(draggedItemId, state.dropTargetItemId);
+                state.dropPlacement = placement;
+                switch (placement) {
+                case UIEditorTreeViewDropPreviewPlacement::BeforeItem:
+                    if constexpr (SupportsSiblingInsertion<Callbacks>()) {
+                        state.validDropTarget =
+                            callbacks.CanInsertBeforeItem(
+                                draggedItemId,
+                                state.dropTargetItemId);
+                    }
+                    break;
+
+                case UIEditorTreeViewDropPreviewPlacement::AfterItem:
+                    if constexpr (SupportsSiblingInsertion<Callbacks>()) {
+                        state.validDropTarget =
+                            callbacks.CanInsertAfterItem(
+                                draggedItemId,
+                                state.dropTargetItemId);
+                    }
+                    break;
+
+                case UIEditorTreeViewDropPreviewPlacement::OnItem:
+                    state.validDropTarget =
+                        callbacks.CanDropOnItem(draggedItemId, state.dropTargetItemId);
+                    break;
+
+                default:
+                    break;
+                }
                 return;
             }
 
+            if constexpr (SupportsSiblingInsertion<Callbacks>()) {
+                UIEditorTreeViewDropPreviewPlacement gapPlacement =
+                    UIEditorTreeViewDropPreviewPlacement::None;
+                const Widgets::UIEditorTreeViewItem* gapItem =
+                    ResolveGapInsertionItem(layout, items, point, gapPlacement);
+                if (gapItem != nullptr &&
+                    gapPlacement != UIEditorTreeViewDropPreviewPlacement::None) {
+                    state.dropTargetItemId = gapItem->itemId;
+                    state.dropPlacement = gapPlacement;
+                    state.validDropTarget =
+                        gapPlacement == UIEditorTreeViewDropPreviewPlacement::BeforeItem
+                            ? callbacks.CanInsertBeforeItem(
+                                draggedItemId,
+                                state.dropTargetItemId)
+                            : callbacks.CanInsertAfterItem(
+                                draggedItemId,
+                                state.dropTargetItemId);
+                    return;
+                }
+            }
+
             if (ContainsPoint(bounds, point)) {
                 state.dropToRoot = true;
+                state.dropPlacement = UIEditorTreeViewDropPreviewPlacement::Root;
                 state.validDropTarget = callbacks.CanDropToRoot(draggedItemId);
             }
         }
@@ -212,11 +346,35 @@ ProcessResult ProcessInputEvents(
 
         bool CommitDrop(State& state, DragDropInteraction::ProcessResult&) {
             droppedToRoot = state.dropToRoot;
-            return state.dropToRoot
-                ? callbacks.CommitDropToRoot(state.draggedItemId)
-                : callbacks.CommitDropOnItem(
+            switch (state.dropPlacement) {
+            case UIEditorTreeViewDropPreviewPlacement::BeforeItem:
+                if constexpr (SupportsSiblingInsertion<Callbacks>()) {
+                    return callbacks.CommitInsertBeforeItem(
+                        state.draggedItemId,
+                        state.dropTargetItemId);
+                }
+                return false;
+
+            case UIEditorTreeViewDropPreviewPlacement::AfterItem:
+                if constexpr (SupportsSiblingInsertion<Callbacks>()) {
+                    return callbacks.CommitInsertAfterItem(
+                        state.draggedItemId,
+                        state.dropTargetItemId);
+                }
+                return false;
+
+            case UIEditorTreeViewDropPreviewPlacement::Root:
+                return callbacks.CommitDropToRoot(state.draggedItemId);
+
+            case UIEditorTreeViewDropPreviewPlacement::OnItem:
+                return callbacks.CommitDropOnItem(
                     state.draggedItemId,
                     state.dropTargetItemId);
+
+            case UIEditorTreeViewDropPreviewPlacement::None:
+            default:
+                return false;
+            }
         }
     } adaptedCallbacks{ layout, items, bounds, callbacks };
 
diff --git a/new_editor/include/XCEditor/Collections/UIEditorTreeView.h b/new_editor/include/XCEditor/Collections/UIEditorTreeView.h
index f49e44f2..931b2ea0 100644
--- a/new_editor/include/XCEditor/Collections/UIEditorTreeView.h
+++ b/new_editor/include/XCEditor/Collections/UIEditorTreeView.h
@@ -164,6 +164,14 @@ void AppendUIEditorTreeView(
 
 namespace XCEngine::UI::Editor {
 
+enum class UIEditorTreeViewDropPreviewPlacement : std::uint8_t {
+    None = 0,
+    OnItem,
+    BeforeItem,
+    AfterItem,
+    Root
+};
+
 bool HasUIEditorTreeViewValidBounds(
     const ::XCEngine::UI::UIRect& bounds);
 
@@ -200,6 +208,17 @@ void UpdateUIEditorTreeViewInlineRenameSession(
     const ::XCEngine::UI::UIRect& bounds,
     const std::vector<::XCEngine::UI::UIInputEvent>& inputEvents);
 
+void AppendUIEditorTreeViewDropPreview(
+    ::XCEngine::UI::UIDrawList& drawList,
+    const Widgets::UIEditorTreeViewLayout& layout,
+    const std::vector<Widgets::UIEditorTreeViewItem>& items,
+    bool active,
+    UIEditorTreeViewDropPreviewPlacement placement,
+    std::string_view dropTargetItemId,
+    const ::XCEngine::UI::UIColor& previewColor,
+    float borderThickness = 1.0f,
+    float cornerRounding = 0.0f);
+
 void AppendUIEditorTreeViewDropPreview(
     ::XCEngine::UI::UIDrawList& drawList,
     const Widgets::UIEditorTreeViewLayout& layout,
diff --git a/new_editor/src/Collections/UIEditorTreeView.cpp b/new_editor/src/Collections/UIEditorTreeView.cpp
index c941661d..decd7fde 100644
--- a/new_editor/src/Collections/UIEditorTreeView.cpp
+++ b/new_editor/src/Collections/UIEditorTreeView.cpp
@@ -516,7 +516,7 @@ void AppendUIEditorTreeViewDropPreview(
     const Widgets::UIEditorTreeViewLayout& layout,
     const std::vector<Widgets::UIEditorTreeViewItem>& items,
     bool active,
-    bool dropToRoot,
+    UIEditorTreeViewDropPreviewPlacement placement,
     std::string_view dropTargetItemId,
     const ::XCEngine::UI::UIColor& previewColor,
     float borderThickness,
@@ -525,7 +525,7 @@ void AppendUIEditorTreeViewDropPreview(
         return;
     }
 
-    if (dropToRoot) {
+    if (placement == UIEditorTreeViewDropPreviewPlacement::Root) {
         drawList.AddRectOutline(
             layout.bounds,
             previewColor,
@@ -541,8 +541,58 @@ void AppendUIEditorTreeViewDropPreview(
         return;
     }
 
-    drawList.AddRectOutline(
-        layout.rowRects[visibleIndex],
+    const UIRect& rowRect = layout.rowRects[visibleIndex];
+    switch (placement) {
+    case UIEditorTreeViewDropPreviewPlacement::OnItem:
+        drawList.AddRectOutline(
+            rowRect,
+            previewColor,
+            borderThickness,
+            cornerRounding);
+        break;
+
+    case UIEditorTreeViewDropPreviewPlacement::BeforeItem:
+        drawList.AddLine(
+            ::XCEngine::UI::UIPoint(rowRect.x, rowRect.y),
+            ::XCEngine::UI::UIPoint(rowRect.x + rowRect.width, rowRect.y),
+            previewColor,
+            borderThickness);
+        break;
+
+    case UIEditorTreeViewDropPreviewPlacement::AfterItem:
+        drawList.AddLine(
+            ::XCEngine::UI::UIPoint(rowRect.x, rowRect.y + rowRect.height),
+            ::XCEngine::UI::UIPoint(rowRect.x + rowRect.width, rowRect.y + rowRect.height),
+            previewColor,
+            borderThickness);
+        break;
+
+    case UIEditorTreeViewDropPreviewPlacement::None:
+    case UIEditorTreeViewDropPreviewPlacement::Root:
+    default:
+        break;
+    }
+}
+
+void AppendUIEditorTreeViewDropPreview(
+    ::XCEngine::UI::UIDrawList& drawList,
+    const Widgets::UIEditorTreeViewLayout& layout,
+    const std::vector<Widgets::UIEditorTreeViewItem>& items,
+    bool active,
+    bool dropToRoot,
+    std::string_view dropTargetItemId,
+    const ::XCEngine::UI::UIColor& previewColor,
+    float borderThickness,
+    float cornerRounding) {
+    AppendUIEditorTreeViewDropPreview(
+        drawList,
+        layout,
+        items,
+        active,
+        dropToRoot
+            ? UIEditorTreeViewDropPreviewPlacement::Root
+            : UIEditorTreeViewDropPreviewPlacement::OnItem,
+        dropTargetItemId,
         previewColor,
         borderThickness,
         cornerRounding);