Two methods of teacher evaluation, summative evaluation and formative evaluation, are examined. The summative theory calls for an assessment of teaching competence on the basis of which judgments may be made on matters pertaining to promotion, tenure, merit salary increments, or dismissal. Summative evaluation is strongly supported because it provides protection against arbitrary decision making about personnel. However, there are drawbacks to this evaluation theory. Without a clearly articulated theory of teaching, there are many possibilities for errors of judgment on the part of the evaluators. Another problematic feature of summative evaluation is seen to lie with its bureaucratic consequences. Formative evaluation calls for the improvement of teaching through self-identification of a teacher's strengths and weaknesses through interaction and feedback. At each step of the evaluation process, the teacher improves performance, based on regular feedback which increases teacher effectiveness. In this approach, care is taken to avoid ranking the teacher or making judgments about the teacher's ability. The merits and drawbacks of each of these evaluation methods are discussed, and practical implications are considered. (JD)