If you are unfamiliar with the City State it is a bare bones, house by house, description of an entire city. Every lord, merchant, thief and hooker gets full stats and a brief description. Plenty to build upon, but not so much that you feel your creativity being stifled. Easy to slip into an existing campaign, or to use as a jumping off point for a new one, or several new ones. You could run three simultaneous campaigns out of here and have a high probability that they'd never cross paths. The additional, essentially blank, player map of the city allows your players to make notations of important locals, and now that we can print it off you can give them several copies for different information. Or no copies and make them squirrel it all out on their own.
The only thing I miss in this product is a full sheet version of the GM and players maps of the city. You can print out the several sheet version and tape it together, but I'd love to be able to run down to the local office store and print out one big one.
[4 of 5 Stars!]