The American social welfare field is best characterized as a highly decentralized sphere of activity in which autonomous organizations define and pursue their goals in a fairly independent fashion. The complex nature of modern social problems, however, requires concerted action by a variety of organizations if effective solutions are to be developed. This conflict between the structural nature of the welfare field and the demands of the problems to be addressed has meant that social welfare planners have had to be concerned with the conditions affecting the willingness of independent organizations to engage in cooperative activities with each other. The purposes of the present paper are twofold: (1) To identify some of the major variables that affect the interorganizational activities of social welfare organizations; and (2) to describe the actual interorganizational patterns of one such organization, a county board of public assistance.