diff --git a/Perspex.Base/PerspexList.cs b/Perspex.Base/PerspexList.cs
index 80fdaeb37d..d0e975427c 100644
--- a/Perspex.Base/PerspexList.cs
+++ b/Perspex.Base/PerspexList.cs
@@ -100,21 +100,21 @@ namespace Perspex
         {
             int index = this.inner.Count;
             this.inner.Add(item);
-            this.NotifyAdd(new[] { item });
+            this.NotifyAdd(new[] { item }, index);
         }
 
         public void AddRange(IEnumerable<T> items)
         {
             int index = this.inner.Count;
             this.inner.AddRange(items);
-            this.NotifyAdd((items as IList) ?? items.ToList());
+            this.NotifyAdd((items as IList) ?? items.ToList(), index);
         }
 
         public void Clear()
         {
             var old = this.inner;
             this.inner = new List<T>();
-            this.NotifyRemove(old);
+            this.NotifyRemove(old, 0);
         }
 
         public bool Contains(T item)
@@ -140,20 +140,27 @@ namespace Perspex
         public void Insert(int index, T item)
         {
             this.inner.Insert(index, item);
-            this.NotifyAdd(new[] { item });
+            this.NotifyAdd(new[] { item }, index);
         }
 
         public void InsertRange(int index, IEnumerable<T> items)
         {
             this.inner.InsertRange(index, items);
-            this.NotifyAdd((items as IList) ?? items.ToList());
+            this.NotifyAdd((items as IList) ?? items.ToList(), index);
         }
 
         public bool Remove(T item)
         {
-            bool result = this.inner.Remove(item);
-            this.NotifyRemove(new[] { item });
-            return result;
+            int index = this.inner.IndexOf(item);
+
+            if (index != -1)
+            {
+                this.inner.RemoveAt(index);
+                this.NotifyRemove(new[] { item }, index);
+                return true;
+            }
+
+            return false;
         }
 
         public void RemoveAll(IEnumerable<T> items)
@@ -162,20 +169,16 @@ namespace Perspex
 
             foreach (var i in items)
             {
-                if (this.inner.Remove(i))
-                {
-                    removed.Add(i);
-                }
+                // TODO: Optimize to only send as many notifications as necessary.
+                this.Remove(i);
             }
-
-            this.NotifyRemove(removed);
         }
 
         public void RemoveAt(int index)
         {
             T item = this.inner[index];
             this.inner.RemoveAt(index);
-            this.NotifyRemove(new[] { item });
+            this.NotifyRemove(new[] { item }, index);
         }
 
         int IList.Add(object value)
@@ -225,11 +228,11 @@ namespace Perspex
             return this.inner.GetEnumerator();
         }
 
-        private void NotifyAdd(IList t)
+        private void NotifyAdd(IList t, int index)
         {
             if (this.CollectionChanged != null)
             {
-                var e = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, t);
+                var e = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, t, index);
                 this.CollectionChanged(this, e);
             }
 
@@ -244,11 +247,11 @@ namespace Perspex
             }
         }
 
-        private void NotifyRemove(IList t)
+        private void NotifyRemove(IList t, int index)
         {
             if (this.CollectionChanged != null)
             {
-                var e = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, t);
+                var e = new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, t, index);
                 this.CollectionChanged(this, e);
             }
 
diff --git a/Perspex.Diagnostics/DevTools.cs b/Perspex.Diagnostics/DevTools.cs
index dcdb030ef6..0fa9c56ca1 100644
--- a/Perspex.Diagnostics/DevTools.cs
+++ b/Perspex.Diagnostics/DevTools.cs
@@ -8,6 +8,7 @@ namespace Perspex.Diagnostics
 {
     using Perspex.Controls;
     using System.Reactive.Linq;
+    using Perspex.Diagnostics.ViewModels;
 
     public class DevTools : Decorator
     {
@@ -29,9 +30,19 @@ namespace Perspex.Diagnostics
                     {
                         DataTemplates = new DataTemplates
                         {
-                            new TreeDataTemplate<IVisual>(GetHeader, x => x.VisualChildren),
+                            new TreeDataTemplate<VisualTreeNode>(GetHeader, x => x.Children),
                         },
-                        [!TreeView.ItemsProperty] = this[!DevTools.RootProperty].Select(x => new[] { x }),
+                        [!TreeView.ItemsProperty] = this[!DevTools.RootProperty].Select(x =>
+                        {
+                            if (x != null)
+                            {
+                                return new[] { new VisualTreeNode((IVisual)x) };
+                            }
+                            else
+                            {
+                                return null;
+                            }
+                        }),
                     }
                 }
             };
@@ -43,16 +54,15 @@ namespace Perspex.Diagnostics
             set { this.SetValue(RootProperty, value); }
         }
 
-        private static Control GetHeader(IVisual visual)
+        private static Control GetHeader(VisualTreeNode node)
         {
-            Control control = visual as Control;
             TextBlock result = new TextBlock();
-            result.Text = visual.GetType().Name;
+            result.Text = node.Type;
 
-            if (control != null && control.TemplatedParent != null)
-            {
-                result.FontStyle = Media.FontStyle.Italic;
-            }
+            //if (control != null && control.TemplatedParent != null)
+            //{
+            //    result.FontStyle = Media.FontStyle.Italic;
+            //}
 
             return result;
         }
diff --git a/Perspex.Diagnostics/Perspex.Diagnostics.csproj b/Perspex.Diagnostics/Perspex.Diagnostics.csproj
index ed7c41e824..d90cf13d74 100644
--- a/Perspex.Diagnostics/Perspex.Diagnostics.csproj
+++ b/Perspex.Diagnostics/Perspex.Diagnostics.csproj
@@ -69,8 +69,12 @@
     <Compile Include="DevTools.cs" />
     <Compile Include="Debug.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="ViewModels\VisualTreeNode.cs" />
   </ItemGroup>
   <ItemGroup>
+    <Reference Include="ReactiveUI">
+      <HintPath>..\packages\reactiveui-core.6.0.7\lib\Portable-Net45+Win8+WP8+WPA81\ReactiveUI.dll</HintPath>
+    </Reference>
     <Reference Include="Splat">
       <HintPath>..\packages\Splat.1.5.0\lib\Portable-net45+win+wpa81+wp80\Splat.dll</HintPath>
     </Reference>
diff --git a/Perspex.Diagnostics/ViewModels/VisualTreeNode.cs b/Perspex.Diagnostics/ViewModels/VisualTreeNode.cs
new file mode 100644
index 0000000000..43238c1c48
--- /dev/null
+++ b/Perspex.Diagnostics/ViewModels/VisualTreeNode.cs
@@ -0,0 +1,22 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using ReactiveUI;
+
+namespace Perspex.Diagnostics.ViewModels
+{
+    internal class VisualTreeNode : ReactiveObject
+    {
+        public VisualTreeNode(IVisual visual)
+        {
+            this.Children = visual.VisualChildren.CreateDerivedCollection(x => new VisualTreeNode(x));
+            this.Type = visual.GetType().Name;
+        }
+
+        public IReactiveDerivedList<VisualTreeNode> Children { get; private set; }
+
+        public string Type { get; private set; }
+    }
+}
diff --git a/Perspex.Diagnostics/packages.config b/Perspex.Diagnostics/packages.config
index e99a951913..feccef7220 100644
--- a/Perspex.Diagnostics/packages.config
+++ b/Perspex.Diagnostics/packages.config
@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
+  <package id="reactiveui" version="6.0.7" targetFramework="portable-net45+win" />
+  <package id="reactiveui-core" version="6.0.7" targetFramework="portable-net45+win" />
   <package id="Rx-Core" version="2.2.5" targetFramework="portable-net45+win" />
   <package id="Rx-Interfaces" version="2.2.5" targetFramework="portable-net45+win" />
   <package id="Rx-Linq" version="2.2.5" targetFramework="portable-net45+win" />
diff --git a/TestApplication/TestApplication.csproj b/TestApplication/TestApplication.csproj
index 5712670957..35a86bae38 100644
--- a/TestApplication/TestApplication.csproj
+++ b/TestApplication/TestApplication.csproj
@@ -36,6 +36,10 @@
     <StartupObject />
   </PropertyGroup>
   <ItemGroup>
+    <Reference Include="ReactiveUI, Version=6.0.7.0, Culture=neutral, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\packages\reactiveui-core.6.0.7\lib\Net45\ReactiveUI.dll</HintPath>
+    </Reference>
     <Reference Include="SharpDX, Version=2.6.2.0, Culture=neutral, PublicKeyToken=b4dcf0f35e5521f1, processorArchitecture=MSIL">
       <SpecificVersion>False</SpecificVersion>
       <HintPath>$(SharpDXPackageBinDir)\SharpDX.dll</HintPath>
@@ -71,12 +75,16 @@
       <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Rx-PlatformServices.2.2.5\lib\net45\System.Reactive.PlatformServices.dll</HintPath>
     </Reference>
+    <Reference Include="System.Reactive.Windows.Threading">
+      <HintPath>..\packages\Rx-XAML.2.2.5\lib\net45\System.Reactive.Windows.Threading.dll</HintPath>
+    </Reference>
     <Reference Include="System.Windows.Forms" />
     <Reference Include="System.Xml.Linq" />
     <Reference Include="System.Data.DataSetExtensions" />
     <Reference Include="Microsoft.CSharp" />
     <Reference Include="System.Data" />
     <Reference Include="System.Xml" />
+    <Reference Include="WindowsBase" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="App.cs" />
diff --git a/TestApplication/packages.config b/TestApplication/packages.config
index b24375491e..ab650ab5ac 100644
--- a/TestApplication/packages.config
+++ b/TestApplication/packages.config
@@ -1,10 +1,13 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
+  <package id="reactiveui" version="6.0.7" targetFramework="net45" />
+  <package id="reactiveui-core" version="6.0.7" targetFramework="net45" />
   <package id="Rx-Core" version="2.2.5" targetFramework="net45" />
   <package id="Rx-Interfaces" version="2.2.5" targetFramework="net45" />
   <package id="Rx-Linq" version="2.2.5" targetFramework="net45" />
   <package id="Rx-Main" version="2.2.5" targetFramework="net45" />
   <package id="Rx-PlatformServices" version="2.2.5" targetFramework="net45" />
+  <package id="Rx-XAML" version="2.2.5" targetFramework="net45" />
   <package id="SharpDX" version="2.6.2" targetFramework="net45" />
   <package id="SharpDX.Direct2D1" version="2.6.2" targetFramework="net45" />
   <package id="SharpDX.DXGI" version="2.6.2" targetFramework="net45" />