A Land of incredible natural resources, the South American continent is rich in plant and animal species. Among birds alone, over 3,100 species are either resident or migrant. Birds are some of South America's treasures and also one of its most endangered resources. Hence the need for a descriptive record of South American birds that will serve both professional and amateur bird students and encourage conservation of these magnificent species. The Birds of South America, when completed, will be a four-volume work. The initial volume, The Oscine Passerines, is the first modern field handbook for all the true songbirds, encompassing over 700 species. Thirty-one color plates by Guy Tudor, meticulously researched for soft-part colors and perching attitudes, provide a definitive visual record of most of the species included and are arranged to show relationships of different species to each other. The text by Robert Ridgely provides extensive information on the habitat, range, habits, and voices of the birds. Over 700 specially prepared distribution maps, based on published sources and recent observations, enhance the volume's usefulness in the field. The other three volumes in the series will repeat this format.