This book is quite simply contains the best information on the subject of indexing.
It tracks the beginnings of index products and pays respects to the pioneers that developed this type of investing. Mr. Shoenfeld thoroughly decribes the myriad of vehicles that are available for investors today (this list grows every day it seems).
But what really makes this book shine is the real-life examples and guest writers. Books about investment theory often lack concrete illustrations of the theories they espouse. Mr. Shoenfeld descibes in detail how and why individual investors, pension plans, and hedge funds use index products. In many cases, fund managers write the chapters. Getting this information "from the horse's mouth" allows insight into thought processes of those responsible for investing millions of dollars.
The scope of the book is amazing, and even more is available on the e-ppendix on the Web. Congratulations to the author on putting together a massive reference book on the subject of indexing.