"A true triumph of information and design. Among the best field guides to any region, this book shows all birds in flight. Its coverage of rarities is less thorough than that of the Nat Geo guide, however. The smaller, Eastern and Western volumes are good, too, and include more information on behavior, but their format made it impossible to reproduce the ingenious design of "big Sibley.""
"The standard reference for plumages and molts; intended in the first instance for banders and museum workers, but intermediate, advanced, or ambitious birders will find a great deal here to help with field identification, too."