More than 10 years in the making, David Sibley's Guide to Birds is a monumental achievement. The beautiful watercolor illustrations (6,600, covering 810 species in North America) and clear, descriptive text place Sibley and his work squarely in the tradition of John James Audubon and Roger Tory Peterson; more than a birdwatcher and evangelizer, he is one of the foremost bird painters and authorities in the U.S.

How does it differ from earlier guides? When Sibley himself was asked, he replied: "My book relies much more on illustrations... I believe the average field guide user spends the vast majority of time looking at the pictures, and when I was developing this layout I based it on the premise that most of the text in current field guides is redundant.... I wanted a book that would condense a huge amount of information into a portable size, and at the same time make the information 'patterned,' logical, and accessible to any reader."

The Sibley Guide to Birds provides a wealth of new information:

• Captioned illustrations show many previously unpublished field marks and revisions of known marks
• Nearly every species is shown in flight
• Measurements include length, wingspan, and weight for every species
• Subspecies and geographic varients are covered thoroughly
• Complete voice descriptions are included for every species
• Maps show the complete distribution of every species: summer and winter ranges, migration routes, and rare occurrences