This report details a study designed to test the sustainability of a school-based Collaborative Action Team (CAT) process, which attempted to address the need to enhance family and community involvement in education and to be self-sustaining over time. Based in communities across five Southwestern states, the intervention tested the sustainability of collaborative partnerships among families, community members, school personnel, and students and the efficacy of this intervention to improve student success. Training for CAT participants consisted of activities to improve their knowledge of, skills in, and attitudes toward collaboration and shared leadership. Qualitative and quantitative measures were used to evaluate and continually refine the CAT process. Data collected provided information on site characteristics, implementation and sustainability of the process, the sustainability of team collaboration, and student outcomes. Overall, results indicated that the development of school-based, collaborative partnerships was an effective way to improve results for students and families in school communities. Establishment of a core team of representative partners was possible with appropriate time and support. Most partnerships were sustained for 1-4 years, with numerous goals accomplished. Forms and data from the intervention are appended. (Contains 26 references.) (SM)