Designed as a resource for local school administrators, the report describes the experiences of 15 local special education agencies in providing related services at reasonable cost through interagency cooperation. An introductory chapter discusses the role of interagency committees (both policy and direct service types), and provides information on five local education agencies (LEA sites) with successful interagency networks. The importance of clarifying roles and responsibilities regarding needs and standards, resource allocations, and procedures is emphasized, and the example of one LEA's interagency agreement is offered. Joint funding considerations are analyzed and examples of five sites' approaches are given. Four site descriptions illustrate methods for pooling resources. A concluding chapter reviews potential problems in the interdisciplinary approach and ways to solve them. Each of the descriptions of model sites includes information on development and results as well as the name and address of a contact person. (CL)