This book will get you to "think visually" whenever you look at a printed page. More than to just recognize the good, bad and plain 'ol ugly, you'll learn techinques to make any document you produce compelling and a joy to read.
My day job includes producing proposals of anywhere from 6 to 100 pages, and since I first read this book about a year ago, I've been getting raves from clients that they always want to pick my stuff up first from the piles they recieve.
Another plus is that all of Robin William's books are clearly, concisely and compactly composed. They are a joy to read, especially after slogging so many 300-500 page desktop design books.