Although I am currently reading "The 80/20 Principle" by Mr Koch, I have this one in electronic format, so I thought I'd post it for your reading pleasure (download).
If you already have read the "80/20 Principle" by the same author, then this book will provide you with only 20% additional information. Mind you, the "80/20 Principle" contained 80% of the most valuable information you need to know about the 80/20 Principle. If you have yet to read the first book, however, this book will contain most of the valuable information contained in the first one and some more.
The additional 20% information is related to how you can APPLY the 80/20 principle to improve your life. Most of it is common sense, but it may help some. The author claims he wrote this book becaue one man told him he couldn't understand the 80/20 principle. If you are one of those, this book is a better read than the "80/20 Principle" since this book seems to be written for those with 8th grade reading level.