diff --git a/README.md b/README.md
index 0eab5d1..f4fff90 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ create animation sequences or simply use the cube as an [XFD][4] device.
 ## Building
 
 The project consists of two parts: The LED cube and the controller PCB. Both parts can
-be build completely separate.
+be build completely separate but need to work together.
 
 * The Cube is a little bit tricky to solder. To see which wire should be bend
   and solder in which direction, use the [3D STL model][12] for reference. To