This pre-post examination of data from the National Surgical Quality Improvement Program found no differences in serious morbidity or mortality within 30 days following surgery across multiple surgical specialties in the 2 years after 2011 ACGME duty hour reform, compared to the last year prior to reform. Although duty hour reform does not appear to be a high-yield strategy for improving surgical outcomes, concerns about worsening procedural skills and increased handoffs leading to patient harm were not borne out in the current data.