The volume of traditional television viewing is still vast but for some broadcasters it is falling far faster than it is being replaced by online delivery, while other uses of the television are growing rapidly. When we can watch something later, we may end up never seeing a programme we otherwise might have enjoyed. When we can watch something else instead, we may not see programmes we would have previously viewed. The problem of prominence for public service broadcasting is that when we can watch what we want, when we want, we may not even see programmes we might have previously watched.