Surgeons write 1.8% of all prescriptions and 9.8% of all opioid prescriptions. Of a total of 180 patients (median age 63 years), 127 did not receive opioids; 53 were prescribed opioids against protocol. The operating surgeon was the only variable independently correlated with protocol adherence. Ambulatory breast surgery patients tolerated a nonopioid pain regimen well. Surgeons' decisions, rather than patient characteristics, primarily drove the choice of pain management in our study.