every time I play it! It is done to stop pirating, is my understanding. Steam can detect if it is an illegal copy. As I have bought Halflife 2, as well as Halflife 1, and don't use illegal copies of the game, it is a pain to connect each time, especially if the servers at Steam are busy and I can't connect. I have a cable modem connection so the actual download times are short once it connects. I would not have bought the game if I realized that even after initial activation, I still needed to go on-line every time to play it. That said, it is an incredible game!