Surgical proficiency gained from performing a higher volume of certain procedures is associated with fewer errors. This study used data from the National Surgical Quality Improvement Program to examine uncommon procedures and their surgical complication rates, with and without trainee participation. As expected, uncommon operations entailed significant rates of morbidity and mortality. Resident involvement was associated with higher likelihood that a patient in distress would be successfully resuscitated but was also associated with a longer operative time. The authors suggest that simulation training for uncommon procedures for residents may improve outcomes. A PSNet perspective reflected on patient safety in surgery.