This paper discusses the most relevant issues concerning teacher evaluation in primary and secondary education by reviewing the recent literature and analysing current practices within the OECD countries. First, it provides a conceptual framework highlighting key features of teacher evaluation schemes. In particular, it emphasises the importance of clarifying the purposes of teacher appraisal, whether summative when designed to assure that the practices enhancing student learning are undertaken or formative when conducted for further professional development objectives. It also encompasses the diverse criteria and instruments commonly used to assess teachers as well as the actors generally involved in the process and potential consequences for teachers' professional life. Second, it deals with a number of contentious points, including the question of the use of student outcomes to measure teaching performance, the advantages and drawbacks of different approaches given the purpose emphasised and resource restrictions, the implementation difficulties resulting from different stakeholders' interests and possible ways to overcome these obstacles. Finally, it provides an account of current empirical evidence, pointing out mixed results stemming from difficulties in assessing the effects of such evaluation schemes on teaching quality, teachers' motivation and student learning. It concludes by considering the circumstances under which teacher evaluation systems seem to be more effective, fair and reliable. Developing a comprehensive approach to evaluate teachers is critical to make demands for educational best practice compatible with teachers' appropriation of the process as well as to enhance the decisive attractiveness and recognition of the teaching profession. (Contains 1 table.)