Background. The current resident selection process relies heavily on medical student performance, with the assumption that analysis of this performance will aid in the selection of successful residents. Although there is abundant literature analyzing indicators of medical student performance measures as predictors of success in residency, wide-ranging differences in beliefs persist concerning their validity. Objective: We sought to collect and review studies that have correlated medical student performance with residency performance. Methods: The English-language literature from 1996 to 2009 was searched with PubMed. Selected studies evaluated medical students on the basis of US Medical Licensing Examination scores, preclinical and clinical performance, research experience, objective structured clinical examination performance, medical school factors, honor society membership, Medical Student Performance Evaluations, letters of recommendation, and faculty interviews. Outcome measures were standardized residency examinations and residency supervisor ratings. Results: The medical student factors that correlated most strongly with performance on examinations in residency were medical student examination scores, clinical performance, and honor society membership. Those that correlated most strongly with supervisor ratings were clinical grades, faculty interview, and medical school attended. Overall, there were inconsistent results for most performance measures. Limitations: In addition to the lack of a widely used measure of success in residency, most studies were small, single institution, and single specialty, and thus of limited ability to generalize findings. Conclusion: No one medical student factor can be used to predict performance in residency. There is a need for a more consistent and systematic approach to determining predictors of success in residency. (J Am Acad Dermatol 2011;65:1010-22.)