Yeah -- his book Off the Books: The Underground Economy of the Urban Poor is pretty good: http://www.amazon.com/Off-Books-Underground-Economy-Urban/dp... . He's a very interesting guy, and I'm not surprised that he's decided to look at prostitution more carefully because it's pretty hard to argue that high-end prostitutes are being exploited or whatever. When I say high-end, think Belle de Jour: http://belledejour-uk.blogspot.com/ , who is compulsively readable and hilarious.