Although this book is out of print, you can find it on ebay.
I credit the principles in this book for helping me lose 60 pounds in my early 20's (I took a moderate rather than strict approach, and I lost ~10-12 pounds per year over a period of 5-6 years). I have kept most of the weight off (50 pounds), for 3 decades with a few times up/down 10 pounds.
I love that it's a simple program that does not rely on any special diet. The basic philosophy is eat what you want only when hungry just until you feel satisfied. I think we would be a much healthier nation if we got back in touch with hunger.
We already know from the French that you can eat rich and decadent foods and stay thin... it ends up coming down to more moderate habits... smaller quantities and at times you would naturally feel hungry (breakfast, lunch, dinner). Anyway, I've had a little up/down fight with 10-15 extra pounds for about a decade now and am turning back to this book to help me get back on track.
If you are tired of dieting, but want to find something that can help you be healthier and your naturally thin self, I highly recommend this book for significan and permanent weight loss.
Maybe I'll add an update after a few months or so of re-focusing on the program. In my early 50's, it all seems to stick, and I can't get away with excessive and emotional eating without gaining weight.
An extremely helpful book that is no longer in print. Fortunately I got a copy at a used bookstore. It's a program I've used successfully through the years, then I forget to implement the principles. Recently I picked it up to reread and practice yet again. I really like her 30-day program.