Objective: The authors performed this study to determine whether clerkship peer evaluations, initiated as part of our "team-based learning" curriculum in 2002, correlated with other student performance measures, and to determine what qualities students rate in their peer evaluations. Method: The authors correlated peer evaluation scores with other student performance measures and performed a qualitative examination of student comments to assess reasons students gave for giving high and low scores. Results: Peer evaluation scores correlated modestly with the National Board of Medical Examiners' (NBME) subject test, in-class quiz, and clinical scores. Qualitative comments demonstrated that students made assessments based on three thematic areas: personal attributes, team contributions, and cognitive abilities. Conclusions: Peers' evaluation scores modestly predict which students will perform well on other measures. However, there may be other qualities that are also important factors in peer evaluation. For example, most students value qualities of preparation and participation. Though students sometimes dislike peer evaluations, their assessments may enhance traditional course assessments and complement a comprehensive evaluation strategy.