This paper summarizes research on teacher attitudes and performance under clinical supervision. The literature for comparative studies of inservice personnel (not student teachers) in elementary and secondary schools was extensively searched. The 19 complete and 4 in-progress studies reported are grouped as follows: (1) attitudes toward supervision, (2) effects of training, (3) personnel characteristics, and (4) student achievement. Eight studies examined teachers' attitudes toward supervision, comparing clinically and traditionally supervised groups or recording attitude changes over time. More positive attitudes were found under clinical supervision, but longer-term research is needed for conclusive findings. The six studies (including one in progress) on the effects of training, although difficult to categorize due to varied training emphases, demonstrated a need for adequate training. Five studies (including one in progress) examined characteristics of teachers and/or principals using clinical supervision. This avenue seems unpromising, though research focusing on behavior may be of use. The final four studies (including two in progress) attempted to relate clinical supervision to student achievement. Because of the many conditions affecting achievement, this area is very difficult to assess; the two works in progress may be significant. (MCG)