If I could only own one cookbook, this would be the one. That is because it is the most comprehensive book I own, and it also comes from my favorite source of recipes (Cook's Illustrated, of course.)
Lots (but probaby not a majority) of the recipes in here come from the magazine. Some of them are simplified, just slightly, and some are simplified greatly. Some recipes come from their newer magazine, Cook's Country, and some come from their various cookbooks.
This cookbook does not include the lengthy discussions, how's and why's of the recipes, but just gives you what you really need to know. It is easier to read and follow than any of their other cookbooks, and it has lots and lots of photos, many of which are used to describe technique. I have the first edition, and the pages are a little thin, and it is in a 3 ring binder, so it isn't as sturdy as I might like, so this one may need to be replaced in the future. There is a newer version out now, which I believe is more sturdy.
To see the recipes I have tried from here, click on the "atkcb" label below.