Cross-school observation, which is part of a joint project involving a college education department and two large suburban high schools, is described. The Collaborative Project for School Improvement (CPSI) involves a joint steering committee and joint inservice sessions, as well as shared resources and a student teaching center. Program planning and implementation and outcomes of cross-school observation are considered. Visits by small groups of teachers to the cooperating school were helpful in launching the project. An important factor in the implementation phase was having someone coordinate the arrangements, such as scheduling observations and arranging for substitute teachers. Participating teachers' reactions to the project, which were elicited through interviews, are summarized. Also discussed are other CPSI components: the steering committee, school development seminars, and joint department meetings. New roles for teachers that have arisen out of the program are also considered, including working on the steering committee and serving as on-site student teacher supervisors. The next steps for continued improvement of a program of professional self-renewal are also addressed. The participating schools, all in California, are: Saint Mary's College in Moraga; California High School in San Ramon Valley; and Foothill High School in Alameda County. (SW)