From the rules: Cross Purposes is a game of strategy for two players.You start a game of Cross Purposes with five trains at your House. Your goal is to get all five trains across the board to your Station, and then to get them all back Home. The train tracks might not run from your Home to your Station, but you can switch the tracks so that they will point where you want your trains to go. Sound simple? It is, except that your opponent has a Home and a Station too, and is trying to run trains on the same tracks. Your opponent will be turning the switches so that the paths run in a different direction. This is why you and your opponent are always at Cross Purposes! - BoardGameGeek