Most clerkship evaluation systems give the greatest evaluative weight in deriving grades to some for of evaluation by faculty and housestaff although few studies have been reported concerning which elements of performance are most important or which discriminate best. The results of this study show that a select group of faculty, heavily involved with assessment of student performance, agreed that certain aspects of performance were more important and/or discriminated better between average and superior medicine clerks. We suggest that those aspects of performance be given more consideration when designing curricula, providing student feedback, and assigning grades for medicine clerkships and that medical educators engage faculty and housestaff in the formal discussion of issues surrounding evaluation.