This study investigated the nature of change in nine rural special education resource room teachers, after they had participated in a comprehensive, system-wide staff development program in the principles of effective teaching using the Program for Effective Teaching. Data were gathered through classroom observations, teacher assessments of educational beliefs and sense of teaching efficacy, and ethnographic interviews. Following training, most of the teachers continued to utilize classroom management patterns that were consistent with their original procedures. Those that were using group and teacher-directed instruction routinely before training tended to continue or increase the use of such structures. Also analyzed were the teachers' use of explanation, demonstration, and assignments; teachers' sense of efficacy; and the strength and nature of teacher beliefs. Teachers who found the training model consistent with their role perceptions and philosophy tended to incorporate the model into their teaching procedures. It is concluded that it is necessary for trainers to consider entry behaviors and beliefs when planning comprehensive change efforts. The success of special education staff development in promoting change was found to be affected by several factors--relevance, mutual adaptation in real settings, supportive relationships, and attention to the issues of integration and communication. (JDD)