Well, it's basically about why Roman cities had suburbs, what made those suburbs different from the centre, and what people did with them. I'm setting it in an empire-wide context, so there's some stuff early on about how Greek authors talk about suburbs (using the word proasteion). But most of it is about the western empire, and of course particularly Gaul - in both the high empire and late antiquity. The evidence for the bulk of the discussion is mainly archaeological, so there's lots of pictures and maps. Finally, I close by looking at how an understanding of suburbs can help us look at wider questions, such as the nature of a Roman city, its relationship with the countryside, and the relationship between the provincial elites and Rome.