Professional development should be part of a teacher's job, and schools should make teacher development an integral part of the teacher's normal activities. Because schools are cooperative, collaborative enterprises, teachers should be involved in the establishment of development programs, should have professional responsibility for cooperating with each other to improve practice, and should not be made to compete for rewards. Development programs should eliminate such barriers to teachers' development efforts as (1) funding shortages that deny teachers both in-school time for development and adequate resources for study and professional interaction, and (2) assumptions that teachers should take responsibility for development individually. Examples of methods that fit the criteria suggested include those used in the Scheney High School Teacher Center in Pittsburgh, Pennsylvania; the employment of teachers as mentors rather than as "master teachers"; the engagement of a nonprofessional support staff to leave teachers free for professional concerns; the rescheduling of school time; and perhaps the coordination of in- and out-of-school time for development. The program should be more concerned with enhancing the teacher's professionalism than his/her specific technical skills, should involve an element of accountability, and should focus on pedagogy. (PGD)