The central concern of this volume is to examine the interrelationships between three levels of urban social structure: (1) local public policy-makers, comprised of elected public officials, the heads of major municipal departments, and "civic notables," or persons who play important roles in urban civic life; (2) "institutional agents," or persons who operate on the grass roots levels of important urban structures, for example, policemen, teachers, case workers, retail merchants, and personnel offices of major employers; and (3) rank-and-file black citizens. The design of the study is comparative. Fifteen cities were examined, representing 13 of the 15 major metropolitan areas of the U. S. The historical context is early 1968 when the field work for the study was undertaken. The research described in this volume tends to support three major conclusions: First, the central institutions of different cities treat their black citizens quite differently. Second, black citizens keenly appreciate those differences. Third, the different treatment of blacks from place to place depends on the political strength that they can muster. In cities where blacks are a large proportion of the electorate, municipal administrations tend to be more attentive to black leaders. In cities where blacks are poorly organized or constitute a small minority, black citizens tend to get short shrift. (Author/JM)