diff --git a/OpenRA.Game/OpenRA.Game.csproj b/OpenRA.Game/OpenRA.Game.csproj
index fd235f027a..8f93aea7c9 100644
--- a/OpenRA.Game/OpenRA.Game.csproj
+++ b/OpenRA.Game/OpenRA.Game.csproj
@@ -246,6 +246,8 @@
     <Compile Include="Renderer.cs" />
     <Compile Include="Platform.cs" />
     <Compile Include="GameSpeed.cs" />
+    <Compile Include="GlobalChat.cs" />
+    <Compile Include="Primitives\ObservableList.cs" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="FileSystem\D2kSoundResources.cs" />
diff --git a/OpenRA.Game/Primitives/ObservableList.cs b/OpenRA.Game/Primitives/ObservableList.cs
new file mode 100644
index 0000000000..d104945f63
--- /dev/null
+++ b/OpenRA.Game/Primitives/ObservableList.cs
@@ -0,0 +1,118 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2015 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation. For more information,
+ * see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections;
+using System.Collections.Generic;
+
+namespace OpenRA.Primitives
+{
+	public class ObservableList<T> : IList<T>, IObservableCollection
+	{
+		protected IList<T> innerList;
+
+		public event Action<object> OnAdd = k => { };
+		public event Action<object> OnRemove = k => { };
+
+		// TODO Workaround for https://github.com/OpenRA/OpenRA/issues/6101
+		#pragma warning disable 67
+		public event Action<int> OnRemoveAt = i => { };
+		public event Action<object, object> OnSet = (o, n) => { };
+		#pragma warning restore
+		public event Action OnRefresh = () => { };
+
+		protected void FireOnRefresh()
+		{
+			OnRefresh();
+		}
+
+		public ObservableList()
+		{
+			innerList = new List<T>();
+		}
+
+		public virtual void Add(T item)
+		{
+			innerList.Add(item);
+			OnAdd(item);
+		}
+
+		public bool Remove(T item)
+		{
+			var found = innerList.Remove(item);
+			if (found)
+				OnRemove(item);
+
+			return found;
+		}
+
+		public void Clear()
+		{
+			innerList.Clear();
+			OnRefresh();
+		}
+
+		public void Insert(int index, T item)
+		{
+			innerList.Insert(index, item);
+			OnRefresh();
+		}
+
+		public int Count { get { return innerList.Count; } }
+		public int IndexOf(T item) { return innerList.IndexOf(item); }
+		public bool Contains(T item) { return innerList.Contains(item); }
+
+		public void RemoveAt(int index)
+		{
+			innerList.RemoveAt(index);
+			OnRemoveAt(index);
+		}
+
+		public T this[int index]
+		{
+			get
+			{
+				return innerList[index];
+			}
+
+			set
+			{
+				var oldValue = innerList[index];
+				innerList[index] = value;
+				OnSet(oldValue, value);
+			}
+		}
+
+		public void CopyTo(T[] array, int arrayIndex)
+		{
+			innerList.CopyTo(array, arrayIndex);
+		}
+
+		public IEnumerator<T> GetEnumerator()
+		{
+			return innerList.GetEnumerator();
+		}
+
+		IEnumerator IEnumerable.GetEnumerator()
+		{
+			return innerList.GetEnumerator();
+		}
+
+		public IEnumerable ObservedItems
+		{
+			get { return innerList; }
+		}
+
+		public bool IsReadOnly
+		{
+			get { return innerList.IsReadOnly; }
+		}
+	}
+}