Morbidity and mortality (M&M) conferences are a useful tool for teams to investigate and learn from adverse events. In this observational study, researchers interviewed clinicians attending surgical M&M conferences to explore the types, and recurrence of, lessons learned. Clinicians ascribed most lessons to technical or individual-level issues, and observed the challenges to sustaining changes at a systems-level. Researchers suggest M&M formats should shift to a broader focus to implement and sustain lasting system-level improvements.