This report summarizes the findings of three studies conducted by the Far West Laboratory for Educational Research and Development in San Francisco, California. The first comprised five case studies of school principals. The second synthesized studies on collaborative arrangements for school improvement, and the third is a review of five studies on the role of linking agents in school improvement. The work on public school principals examined the behavior of these individuals in different settings, and showed how community, district, and personal factors interacted with the organizational characteristics of schools to shape instructional management activities and decisions. The review of studies on interorganizational collaboration found that: (1) formal collaborative arrangements are widespread, effective, and influenced by external factors; (2) structure has little influence on effectiveness; and (3) effective collaboration requires strong leadership, mutual ownership of the collaborative effort, congruency of needs and resources among collaborating organizations, and flexible operating procedures. Finally, the study on linking agents indicated that: (1) linkage activities include communication, coordination, resource finding, assistance in information utilization as well as problem solving and program implementation, and administration; (2) support systems were more significant than formal training in shaping linking agents' attitudes and behavior; and (3) linker effectiveness depends on the research focus, external assistance, the nature and magnitude of the innovation, and local support. (MJL)