In September 1986 the Rochester City School District (New York) implemented the Peer Assistance and Review (PAR) Program. This program is a pilot project designed to provide internships to new teachers and intervention to tenured teachers who are in need of assistance. The purpose of peer assisted internships is to help develop and retain effective new teachers. The PAR program pairs new teachers (interns) with experienced teachers (mentors) during their first year in the District. Mentors help interns develop and refine their teaching skills and also acquaint the new teachers with their other teaching responsibilities. This paper presents a description of the program and outlines the salient factors involved in a comprehensive evaluation of the program's effectiveness. The purpose of the evaluation was to: (1) determine whether PAR internships have had an impact on developing and retaining good teachers; (2) provide a mechanism for improving the PAR Program; and (3) document efforts contributing to staff development, student achievement, and teacher professionalism. In describing and discussing the program and its evaluation, reflections are included on the implications for policy formation in the District. (JD)