Agency directors, program administrators and planners as well as U. S. Fish and Wildlife Service regional federal aid supervisors provided input that defined 22 factors considered most important in determining management effectiveness of state fish and wildlife agencies. I grouped the factors into the following six categories: public support and awareness, conflict resolution, politics, planning and funding, agency management and personnel. State agency directors, commissioners and legislators ranked the factors. In cooperation with the U. S. Fish and Wildlife Service and Organization of Wildlife Planners, I conducted case studies of nine state fish and wildlife agencies widely recognized by their peers as being particularly effective relative to the identified factors. Questionnaires and interviews with 845 agency members and constituents revealed effective fish and wildlife agencies had much in common with the excellent companies described by Peters and Waterman (1982) in In Search of Excellence. Effective agencies were proactive in dealing with issues and frequently among the nation's leading agencies in dealing with issues of national scope. Effective agencies used a variety of techniques to understand public desires and involve the public in making important decisions. Effective agencies grant their employees much freedom to make decisions and try new ideas without fear of punishment for making mistakes. They are committed to the personal development of employees. Effective agencies are good planners, with well defined missions and goals. Personal missions of employees are highly congruent with agency missions, resulting ina missionary-like zeal for their work. Effective agencies have a strong biological basis for their decisions and maintain credibility by balancing biological factors with public opinion. Effective agencies have stable political environments and experienced, enlightened resource management professionals as their leaders. Leaders emphasize participative decision making and teamwork. Finally, effective agencies have strong public support and are effective in mobilizing that support when important policy decisions are made. Many specific examples that illustrate the characteristics of effective agencies are discussed. / Ph. D.