Physicians who are disciplined by state licensing boards are more likely to have demonstrated unprofessional behavior in medical school. Information is limited on whether similar performance measures taken during residency can predict performance as practicing physicians. To determine whether performance measures during residency predict the likelihood of future disciplinary actions against practicing internists. Retrospective cohort study. State licensing board disciplinary actions against physicians from 1990 to 2006. 66,171 physicians who entered internal medicine residency training in the United States from 1990 to 2000 and became diplomates. Predictor variables included components of the Residents' Annual Evaluation Summary ratings and American Board of Internal Medicine (ABIM) certification examination scores. 2 performance measures independently predicted disciplinary action. A low professionalism rating on the Residents' Annual Evaluation Summary predicted increased risk for disciplinary action (hazard ratio, 1.7 [95% CI, 1.3 to 2.2]), and high performance on the ABIM certification examination predicted decreased risk for disciplinary action (hazard ratio, 0.7 [CI, 0.60 to 0.70] for American or Canadian medical school graduates and 0.9 [CI, 0.80 to 1.0] for international medical school graduates). Progressively better professionalism ratings and ABIM certification examination scores were associated with less risk for subsequent disciplinary actions; the risk ranged from 4.0% for the lowest professionalism rating to 0.5% for the highest and from 2.5% for the lowest examination scores to 0.0% for the highest. The study was retrospective. Some diplomates may have practiced outside of the United States. Nondiplomates were excluded. Poor performance on behavioral and cognitive measures during residency are associated with greater risk for state licensing board actions against practicing physicians at every point on a performance continuum. These findings support the Accreditation Council for Graduate Medical Education standards for professionalism and cognitive performance and the development of best practices to remediate these deficiencies.