This monograph presents a diagram which distinguishes four different assessment levels in the teacher's professional development. Level 1 refers to assessments of the training experience, level 2 to assessments of the teacher's behavior, level 3 to assessments of pupil behavior, and level 4 to assessments of instruction. The diagram explains that level 4 is influenced by level 3, level 3 by level 2, and level 2 by level 1. It is explained that program decisions based on assessments were traditionally made at level 1. The validity of levels 2, 3, and 4 are then examined. It is held that level 2 is the level at which teaching should be evaluated. It becomes necessary, however, to determine competencies for this evaluation. The document presents a hierarchy of relevant competencies, including broad concepts, general characteristics, and specific behavior items. Program evaluation is also examined, and the statement is made that it must be demonstrated that teacher education programs can produce the kinds of teacher behaviors which in turn produce more growth in pupils. It is then necessary to use pupil behavior in program evaluation. The problems this causes in teacher evaluation can be avoided, however, through the use of large samples. The monograph also discusses lack of knowledge as a weakness in specifying competencies and developing programs. (PB)