The evolution of public transportation systems in the large American cities of the late nineteenth century culminated in the innovation of the streetcar. Such transportation changes affected urban structure and by the last quarter of the century had produced a distinctive residential area, the streetcar suburb. Washington, D.C. had a number of such suburbs, some the result of subdivision development associated with the extension of streetcar lines to link existing village suburbs to the downtown core, others the product of concurrent residential subdivision and streetcar development. Such suburbs were predominantly middle-class, white, residential areas. An examination of two Washington, D.C. suburbs: Brightwood and Brookland, indicated distinct physical, social, economic, and demographic structures in these village suburbs in the early 1880's. After the subsequent introduction of streetcar links to downtown Washington--an employment core characterized by much white-collar government employment--the two suburbs became increasingly similar in terms of the chosen measurements. By the end of the century, there was little in their structures to indicate the very different paths they had taken to the same end.