A Week in the Zone by Barry Sears
IMO, A Week in the Zone is THE "CR" book to start with. It's cheap, succinct & reads fast. It's very portable (fits nicely in a small bag or purse -- so you can sneak it into to your favorite restaurant). And, most important, it introduces you to the "most comfortable" method of doing CR (again, IMHO -- but based on 3 1/2 yrs experience . If you feel comfortable with the diet (i.e. after "a week in the Zone"), and have an interest in the science behind CR, go for Walford's Beyond the 120 Year Diet : How to Double Your Vital Years . Sears more in-depth books, and the original The Zone : Revolutionary Life Plan to Put Your Body in Total Balance for Permanent Weight Loss (not yet reviewed), are also good choices for your CR library.