Vagrant birds capture the imagination of nearly all birders. How did that Dusky Warbler reach California’s Farallon Islands? How did Terry Wahl identify that Solander’s Petrel off Washington? Weren’t Conover and Myers lucky to find that Crowned Slaty Flycatcher in Louisiana? We find ourselves fascinated by a bird’s ability to wander far astray as well as by birders’ abilities to locate and identify these wayward creatures. In 1996, Cottridge and Vinicombe (Rare Birds of Britain and Ireland, HarperCollins Publishers) produced a solid summary of what was known about the mechanisms of bird vagrancy, perhaps the first such summary widely available to birders. Bertholdt’s Bird Migration: A General Survey (2001, Oxford University Press) was both excellent and accessible to non-ornithologists, but devoted little space to errant migration. In 2008, Newton (The Migration Ecology of Birds, Academic Press) penned a truly comprehensive but exhausting discussion of bird migration that is peppered with errors. Despite these resources, avid birders and field ornithologists were still lacking a comprehensive yet concise review of bird migration and vagrancy. That problem has been solved by the publication of an extraordinary book: Rare Birds of North America. This volume provides the keys to understanding how a Dusky Warbler might arrive in central California, how to identify a Solander’s Petrel, and why the finding of a Crowned Slaty Flycatcher in coastal Louisiana might be more than luck.