In 1974, the Massachusetts Audubon Society and the Massachusetts Division of Fisheries and Wildlife launched a five-year survey to map the distribution of all the birds that breed in the Commonwealth - the first such comprehensive effort in North America. Nearly 600 volunteers spent countless hours in the field collecting data. This landmark volume presents the results of their efforts. The book includes distribution maps showing possible, probable, and confirmed breeding areas for 198 Massachusetts nesting species on a grid of 989 tensquare-mile blocks. Opposite each species map is a summary account giving historical perspective, relative abundance, habitat, seasonal schedule, nest, egg, and song descriptions, clutch size, egg dates, number of broods, and other pertinent details. Each species account is illustrated with a scrupulously accurate, watercolor portrait by award-winning nature artists John Sill and Barry Van Dusen. The book also includes a set of six transparent overlay maps in an attached pocket that allow the reader to correlate key environmental factors with the distribution of nesting species. Introductory sections describe the atlas survey methodology, and two appendixes document bird species known to breed in Massachusetts before and after, but not during, the survey period, and list scientific names of plants and animals (other than birds) noted in the text. This is a book that will appeal not just to ornithologists, but to anyone who appreciates the remarkable diversity of bird life in Massachusetts.