Without transport there is no activity in society. Thus transport has been allowed to grow more or less unchecked for decades and even centuries. Environmental concerns seem, however, to be on the brink of changing this for good. While the challenge for technology is to provide radically cleaner vehicles and more efficient transport systems, social policy must tackle ways of making more efficient use of the existing transport infrastructure. That means re-examining many of our working practices and lifestyles, and in particular our right to unrestricted personal mobility.