This has been useful in a limited sort of way, for when I first began trying to identify birds at my feeders. It is limited to the 25 most common birds, and I think only a few times have I seen birds at my feeders that are not in this book. However, I've had to cross-reference with another bird guide many times, as the pictures only give a single view of the bird, though for a few there are smaller insert photos of winter or female markings. The most useful feature for me has been that it's organized by size, with small pictures at the bottom of the page indicating the relative size of the bird, which I find much more helpful than a notation of approximate inches, since I can't exactly get close enough to measure the birds. ( )