The traditional notion of “community” rests on a close mapping of two things: the times and spaces where we live, and our sense (both cognitive and emotional) of commonality, of connection. But for all of us, even if in different ways and to different degrees, those things are being pulled apart. If you have lived, as I have, in an even moderately busy urban street, it makes sense, although a weird kind of sense, that you do not speak to the person who lives two doors down from you, who tends to go to work at the same time as you, even if (as in one bizarre case that happened to me) it turns out that person ends his or her journey to work only a few yards from where you do! On the other hand, it makes sense to show significant pleasure, when at a conference you meet only for the second time someone from a distant university with whom (apart from broad outlines of work specialization) your life and its milieu may have very little in common. So there are good and bad sides, as always, to the stretching of time-space relations! But one effect is that any particular milieu is characterized by what the sociologist Martin Albrow has called “time-space social stratification” (1997: 52): our paths move in parallel with those of countless others we rarely see, so that, even when our paths do cross with theirs, the encounter may seem random rather than meaningful.1