This book is pretty revolutionary,
Verified Purchase(What is this?)
This review is from: Impact Mapping: Making a Big Impact with Software Products and Projects (Paperback)
If you can pick it up cheap enough (which I did) you'll over look its brevity as an issue.
The contents though are accessible and its core messages are revolutionary for product development. Quite simply many many people don't need to be part of projects that are, and many many things don't need to be done.