When designing a PC Board, the signal routing and its return are critical to the circuit working properly. Often, great care is given to routing the signals, but the return portion is the last thing considered, or sometimes it is forgotten altogether. This presentation will talk about the importance of designing that return path with a discussion of the physics involved, where the energy flows, and the planes and stackup needed. We will also look at the spacing that helps prevent problems, the best paths to contain energy, and the routing and return movement from layer to layer. Throughout, we will discuss some signal routes and look at the paths that might set up the best possibility for a clean return.