I'm a huge fan of Leo's Zen Habits blog and this was sitting in my Amazon queue for longer than it should have. This book demonstrates how to streamline your life by identifying the essential and eliminating the unnecessary – freeing you from everyday clutter and allowing you to focus on accomplishing the goals that can change your life for the better. The message is clear, the writing is simple and straightforward and the lessons are powerful.
I don't know why you'd need any other productivity book after reading this one.