Rowan Cahill and I have lived with the idea of this book since December 2001, when Ian Syson, an independent publisher from Melbourne, suggested to us that we might write about Sydney for a series of books on ‘radical cities’ published by his 59 company, Vulgar Books. The organizing idea was a walking tour of about 50 places associated with radical events or people in the city, each site identified on a map, described in a short slab of text, and illustrated by two images: one of the site as it was at the height of its radical notoriety and another as it is today. The first in the series, Radical Melbourne, had sold a couple of thousand copies and Ian was anxious to capitalize on this success.