diff --git a/OpenRa.DataStructures/Delegates.cs b/OpenRa.DataStructures/Delegates.cs
index e8d30a94b5..bc73953c79 100644
--- a/OpenRa.DataStructures/Delegates.cs
+++ b/OpenRa.DataStructures/Delegates.cs
@@ -8,4 +8,6 @@ namespace OpenRa
 	// they are generic.
 
 	public delegate T Provider<T>();
+	public delegate T Provider<T,U>( U u );
+	public delegate T Provider<T,U,V>( U u, V v );
 }
diff --git a/OpenRa.Game/Game.cs b/OpenRa.Game/Game.cs
index 5090bf0f6e..5316d98678 100644
--- a/OpenRa.Game/Game.cs
+++ b/OpenRa.Game/Game.cs
@@ -14,6 +14,10 @@ namespace OpenRa.Game
 		public readonly Viewport viewport;
 		public readonly PathFinder pathFinder;
 		public readonly Network network;
+		public readonly TechTree.TechTree techTree = new TechTree.TechTree();
+
+		// temporary, until we remove all the subclasses of Building
+		public Dictionary<string, Provider<Building, int2, int>> buildingCreation = new Dictionary<string, Provider<Building, int2, int>>();
 
 		public Game(string mapName, Renderer renderer, int2 clientSize)
 		{
@@ -32,6 +36,27 @@ namespace OpenRa.Game
 			pathFinder = new PathFinder(map, terrain.tileSet);
 
 			network = new Network();
+
+			buildingCreation.Add( "fact",
+				delegate( int2 location, int palette )
+				{
+					return new ConstructionYard( location, palette );
+				} );
+			buildingCreation.Add( "proc",
+				delegate( int2 location, int palette )
+				{
+					return new Refinery( location, palette );
+				} );
+			buildingCreation.Add( "powr",
+				delegate( int2 location, int palette )
+				{
+					return new Building( "powr", location, palette );
+				} );
+			buildingCreation.Add( "apwr",
+				delegate( int2 location, int palette )
+				{
+					return new Building( "apwr", location, palette );
+				} );
 		}
 
 		public void Tick()
@@ -41,7 +66,7 @@ namespace OpenRa.Game
 
 		public void Issue(IOrder order)
 		{
-			order.Apply();
+			order.Apply( this );
 		}
 	}
 }
diff --git a/OpenRa.Game/Harvester.cs b/OpenRa.Game/Harvester.cs
index a7f36b439c..3afa52261d 100644
--- a/OpenRa.Game/Harvester.cs
+++ b/OpenRa.Game/Harvester.cs
@@ -51,7 +51,7 @@ namespace OpenRa.Game
 				harvester = harv;
 			}
 
-			public void Apply()
+			public void Apply( Game game )
 			{
 				harvester.AcceptHarvestOrder();
 			}
diff --git a/OpenRa.Game/ISelectable.cs b/OpenRa.Game/IOrderGenerator.cs
similarity index 81%
rename from OpenRa.Game/ISelectable.cs
rename to OpenRa.Game/IOrderGenerator.cs
index 75b73e36f2..6dee93001b 100644
--- a/OpenRa.Game/ISelectable.cs
+++ b/OpenRa.Game/IOrderGenerator.cs
@@ -4,7 +4,7 @@ using System.Text;
 
 namespace OpenRa.Game
 {
-	interface ISelectable
+	interface IOrderGenerator
 	{
 		//Sprite CurrentCursor( int x, int y );
 		IOrder Order( int2 xy );
diff --git a/OpenRa.Game/MainWindow.cs b/OpenRa.Game/MainWindow.cs
index 6aca770271..e233a3ee3d 100644
--- a/OpenRa.Game/MainWindow.cs
+++ b/OpenRa.Game/MainWindow.cs
@@ -48,11 +48,11 @@ namespace OpenRa.Game
 			game.world.Add( new Mcv( new int2( 5, 5 ), 3 ) );
 			game.world.Add( new Mcv( new int2( 7, 5 ), 2 ) );
 			Mcv mcv = new Mcv( new int2( 9, 5 ), 1 );
-			game.world.myUnit = mcv;
+			game.world.orderGenerator = mcv;
 			game.world.Add( mcv );
 			game.world.Add( new Refinery( new int2( 7, 5 ), 2 ) );
 
-			sidebar = new Sidebar(Race.Soviet, renderer, game.viewport);
+			sidebar = new Sidebar(game.techTree, Race.Soviet, renderer, game.viewport);
 
 			renderer.SetPalette( new HardwarePalette( renderer, game.map ) );
 		}
@@ -79,12 +79,15 @@ namespace OpenRa.Game
 				RectangleF rect = new RectangleF(sidebar.Location.ToPointF(), new SizeF(sidebar.Width, game.viewport.Height));
 				if (rect.Contains(point.ToPointF()))
 				{
-					sidebar.Build(sidebar.FindSpriteAtPoint(point));
+					sidebar.Build( sidebar.FindSpriteAtPoint( point ), game );
 					return;
 				}
 				float2 xy = (1 / 24.0f) * point;
-				IOrder order = game.world.myUnit.Order( new int2( (int)xy.X, (int)xy.Y ) );
-				game.Issue( order );
+				if( game.world.orderGenerator != null )
+				{
+					IOrder order = game.world.orderGenerator.Order( new int2( (int)xy.X, (int)xy.Y ) );
+					game.Issue( order );
+				}
 			}
 		}
 
diff --git a/OpenRa.Game/Mcv.cs b/OpenRa.Game/Mcv.cs
index 02c995b37f..b900861875 100644
--- a/OpenRa.Game/Mcv.cs
+++ b/OpenRa.Game/Mcv.cs
@@ -28,8 +28,8 @@ namespace OpenRa.Game
 					world.Add( new ConstructionYard( fromCell - new int2( 1, 1 ), palette ) );
 					world.Add( new Refinery( fromCell - new int2( 1, -2 ), palette ) );
 
-					world.myUnit = new Harvester( fromCell - new int2( 0, -4 ), palette );
-					world.Add( (Actor)world.myUnit );
+					world.orderGenerator = new Harvester( fromCell - new int2( 0, -4 ), palette );
+					world.Add( (Actor)world.orderGenerator );
 				} );
 				currentOrder = null;
 			};
diff --git a/OpenRa.Game/MoveOrder.cs b/OpenRa.Game/MoveOrder.cs
index 70b7755896..8611f756e0 100644
--- a/OpenRa.Game/MoveOrder.cs
+++ b/OpenRa.Game/MoveOrder.cs
@@ -6,7 +6,7 @@ namespace OpenRa.Game
 {
 	interface IOrder
 	{
-		void Apply();
+		void Apply( Game game );
 	}
 
 	class MoveOrder : IOrder
@@ -20,7 +20,7 @@ namespace OpenRa.Game
 			this.Destination = destination;
 		}
 
-		public void Apply()
+		public void Apply( Game game )
 		{
 			Unit.AcceptMoveOrder( Destination );
 		}
@@ -35,7 +35,7 @@ namespace OpenRa.Game
 			this.Mcv = mcv;
 		}
 
-		public void Apply()
+		public void Apply( Game game )
 		{
 			Mcv.AcceptDeployOrder();
 		}
diff --git a/OpenRa.Game/OpenRa.Game.csproj b/OpenRa.Game/OpenRa.Game.csproj
index c94fdabe9d..af135ab1d3 100644
--- a/OpenRa.Game/OpenRa.Game.csproj
+++ b/OpenRa.Game/OpenRa.Game.csproj
@@ -44,6 +44,7 @@
     <Compile Include="Animation.cs" />
     <Compile Include="Building.cs" />
     <Compile Include="Game.cs" />
+    <Compile Include="IOrderGenerator.cs" />
     <Compile Include="Network\Packet.cs" />
     <Compile Include="Sheet.cs" />
     <Compile Include="Harvester.cs" />
@@ -52,7 +53,6 @@
     <Compile Include="PathFinder.cs" />
     <Compile Include="Sequence.cs" />
     <Compile Include="ConstructionYard.cs" />
-    <Compile Include="ISelectable.cs" />
     <Compile Include="MoveOrder.cs" />
     <Compile Include="Region.cs" />
     <Compile Include="SequenceProvider.cs" />
diff --git a/OpenRa.Game/Sidebar.cs b/OpenRa.Game/Sidebar.cs
index 50689d69de..f66a7560e2 100644
--- a/OpenRa.Game/Sidebar.cs
+++ b/OpenRa.Game/Sidebar.cs
@@ -12,7 +12,7 @@ namespace OpenRa.Game
 {
 	class Sidebar
 	{
-		TechTree.TechTree techTree = new TechTree.TechTree();
+		TechTree.TechTree techTree;
 
 		SpriteRenderer spriteRenderer;
 		Sprite blank;
@@ -24,11 +24,12 @@ namespace OpenRa.Game
 		public float Width
 		{
 			get { return spriteWidth * 2; }
-		} 
+		}
 
 
-		public Sidebar(Race race, Renderer renderer, Viewport viewport)
+		public Sidebar( TechTree.TechTree techTree, Race race, Renderer renderer, Viewport viewport )
 		{
+			this.techTree = techTree;
 			this.viewport = viewport;
 			viewport.AddRegion( Region.Create(viewport, DockStyle.Right, 128, Paint));
 			techTree.CurrentRace = race;
@@ -41,9 +42,9 @@ namespace OpenRa.Game
 			blank = SheetBuilder.Add(new Size((int)spriteWidth, (int)spriteHeight), 16);
 		}
 
-		public bool Build(string key)
+		public void Build(string key, Game game )
 		{
-			return techTree.Build(key);
+			game.world.orderGenerator = new PlaceBuilding( 1, key.ToLowerInvariant() );
 		}
 
 		void LoadSprites(string filename)
@@ -117,4 +118,48 @@ namespace OpenRa.Game
 			return null;
 		}
 	}
+
+	class PlaceBuilding : IOrderGenerator
+	{
+		int palette;
+		string buildingName;
+
+		public PlaceBuilding( int palette, string buildingName )
+		{
+			this.palette = palette;
+			this.buildingName = buildingName;
+		}
+
+		public IOrder Order( int2 xy )
+		{
+			// todo: check that space is free
+			return new PlaceBuildingOrder( this, xy );
+		}
+
+		class PlaceBuildingOrder : IOrder
+		{
+			PlaceBuilding building;
+			int2 xy;
+
+			public PlaceBuildingOrder( PlaceBuilding building, int2 xy )
+			{
+				this.building = building;
+				this.xy = xy;
+			}
+
+			public void Apply( Game game )
+			{
+				game.world.AddFrameEndTask( delegate
+				{
+					Provider<Building, int2, int> newBuilding;
+					if( game.buildingCreation.TryGetValue( building.buildingName, out newBuilding ) )
+					{
+						game.world.Add( newBuilding( xy, building.palette ) );
+						game.techTree.Build( building.buildingName );
+					}
+					game.world.orderGenerator = null;
+				} );
+			}
+		}
+	}
 }
diff --git a/OpenRa.Game/Unit.cs b/OpenRa.Game/Unit.cs
index 96fcc5a6e1..d0e08335c2 100644
--- a/OpenRa.Game/Unit.cs
+++ b/OpenRa.Game/Unit.cs
@@ -4,7 +4,7 @@ using System.Text;
 
 namespace OpenRa.Game
 {
-	abstract class Unit : Actor, ISelectable
+	abstract class Unit : Actor, IOrderGenerator
 	{
 		protected Animation animation;
 
diff --git a/OpenRa.Game/World.cs b/OpenRa.Game/World.cs
index 35127926d1..6a311f0bd9 100644
--- a/OpenRa.Game/World.cs
+++ b/OpenRa.Game/World.cs
@@ -14,7 +14,7 @@ namespace OpenRa.Game
 		List<Action<World>> frameEndActions = new List<Action<World>>();
 		SpriteRenderer spriteRenderer;
 		Viewport viewport;
-		public ISelectable myUnit;
+		public IOrderGenerator orderGenerator;
 
 		public World(Renderer renderer, Viewport viewport)
 		{
diff --git a/OpenRa.TechTree/TechTree.cs b/OpenRa.TechTree/TechTree.cs
index a107df9f49..bc741d6b2f 100644
--- a/OpenRa.TechTree/TechTree.cs
+++ b/OpenRa.TechTree/TechTree.cs
@@ -65,8 +65,9 @@ namespace OpenRa.TechTree
 
 		public bool Build(string key, bool force)
 		{
-			if (string.IsNullOrEmpty(key)) return false;
-			Item b = objects[key];
+			if( string.IsNullOrEmpty( key ) ) return false;
+			key = key.ToUpperInvariant();
+			Item b = objects[ key ];
 			if (!force && !b.CanBuild) return false;
 			built.Add(key);
 			CheckAll();
@@ -80,6 +81,7 @@ namespace OpenRa.TechTree
 
 		public bool Unbuild(string key)
 		{
+			key = key.ToUpperInvariant();
 			Item b = objects[key];
 			if (!built.Contains(key)) return false;
 			built.Remove(key);
diff --git a/sequences.xml b/sequences.xml
index 7a5777bf26..b5caf51f05 100644
--- a/sequences.xml
+++ b/sequences.xml
@@ -47,7 +47,23 @@
 		<sequence name="damaged-idle" start="1"/>
 		<sequence name="make" start="0" length="*" src="procmake" />
 	</unit>
+
+	<!-- power plant -->
+
+	<unit name="powr">
+		<sequence name="idle" start="0"/>
+		<sequence name="damaged-idle" start="1"/>
+		<sequence name="make" start="0" length="*" src="powrmake" />
+	</unit>
 	
+	<!-- advanced power plant -->
+
+	<unit name="apwr">
+		<sequence name="idle" start="0"/>
+		<sequence name="damaged-idle" start="1"/>
+		<sequence name="make" start="0" length="*" src="apwrmake" />
+	</unit>
+
 	<!-- mcv -->
 	
 	<unit name="mcv">