This report describes the development and psychometric qualities of a new instrument to assess clinical teaching effectiveness in medical education. The strength of the instrument is seen to lie in the qualitative development process involving iterative checking with key stakeholders; its high reliability, validity, and feasibility; and its ease of implementation within a coherent institution-wide feedback system. The instrument was developed in conjunction with current literature and with data collected from a series of interviews with relevant stakeholders. The instrument has 15 rating items, and one general item asking residents if they would recommend this individual as a clinical teacher. The instrument was implemented in 1997-98 across all 41 clinical departments of the Cleveland (Ohio) Clinic Academic Medical Center. This report presents psychometric data on instrument characteristics, modifying variables, reliability, content validity, criterion-related validity, and feasibility/usefulness. The instrument is found to be potentially useful in instructor evaluation, research on variables affecting clinical teaching, and staff development. (DB)