In two centuries of American ornithology, The Birds of North America (BNA) is only the fourth comprehensive reference covering the life histories of North America’s breeding birds. Following in the footsteps of Wilson, Audubon, and Bent, BNA provides a quantum leap in information beyond what those historic figures were able to assemble. The print version of BNA was completed in 2002 – 18 volumes, 18,000 pages -- a joint 10 year project of the American Ornithologists' Union, the Cornell Lab of Ornithology, and the Academy of Natural Sciences. Now as an online project of the Cornell Lab of Ornithology, BNA is becoming a living resource. Account contents are updated frequently, with contributions from researchers, citizen scientists, and designated reviewers and editors. In addition, BNA Online contains image and video galleries showing plumages, behaviors, habitat, nests and eggs, and more. And most online BNA accounts now feature recordings of the songs and calls of their species, recordings selected from the extensive collection of Cornell's Macaulay Library of Natural Sounds. Future work will enhance BNA’s audio and video contributions, speed revisions via efforts coordinated online, and provide a significant boost to the number of photos available to subscribers. Stay tuned!