Objective: We compared discharges from teaching and nonteaching hospitals for relative rates and likelihood of potentially preventable adverse events. Methods: We applied Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicators (PSIs) to adult male patient discharges from Veterans Health Administration (VA) and non-Federal hospitals, calculated risk-adjusted PSI rates, and compared the likelihood of incurring a PSI event, controlling for case-mix and hospital characteristics. Results: PSI rates were higher in major teaching hospitals than in nonteaching hospitals for iatrogenic pneumothorax and selected infections due to medical care in both VA and non-Federal hospitals and for postoperative pulmonary embolism or deep-vein thrombosis in non-Federal hospitals. In non-Federal hospitals, likelihood of a PSI event was higher in major teaching hospitals for decubitus ulcer and postoperative wound dehiscence in addition to those PSIs with higher stratified rates. Conclusion: Further research is needed on the relationship of residency programs to adverse events. Differences between VA and non-Federal hospitals suggest that if residency programs increase risk to patients, the causes may be actionable at the organizational level.