An ESSENTIAL SUPPLEMENT!
In my opinion, and I know many disagree, the Werewolf core book didn't do enough justice to the possibility of werewolves living in cities. This book takes care of that problem very well, having large sections of the book dedicated to how werewolves fit into the urban or suburban environment, as well as expanded sections on wilderness areas.
Additionally, it allows the Storyteller to make a wolf-blooded character based on a sliding-scale, rather than the absolute presented in the Forsaken core book.
This is a great book. If you buy one supplement for Werewolf the Forsaken, this should be at least in the top three (other two: Lore of the Forsaken and Predators) if not the top position. Especially if you want your characters to be in a city during your story.