-21 that training programs should be held accountable for changing teacher behavior (53:8). Therefore, they claim that Criterion Level 3 is the most appropriate for accountability in teacher education. The objectives of teacher education programs can be integrated with the requirements for professional service in the classroom by using Criterion Level 3 to evaluate the effectiveness of teacher education programs and competencies of individual trainees for certification. Considering the concept of change, Houston identified three assumptions regarding this topic that are relevant to PBTE programs: Behavior is most likely to be changed when: 1. Individuals sense a problem or feel a need for some change in themselves or their environment. 2. Persons who are expected to change behavior are involved in determining where change is needed and the processes by which change can occur; and; 3. Major decisions about the elements of change are made by the persons expecting to implement and maintain the new behavior. (34:117) In order for a PBTE program to maintain relevancy, two areas must be given careful attention according to Houston. "The program must consciously consider and draw on the potentialities of a changing society. Second, the new program philosophy must include the explicit assumption that no program is ever completely developed" (34:118).