Ambulatory care settings are receiving increased attention as a focus for patient safety improvements. Using data from a multistate patient safety organization (PSO) database, the researchers sought to characterize patterns and characteristics of patient safety incidents reported in ambulatory care settings. Analyses found that 5.9% of events resulted in severe harm and 1.9% resulted in patient death. Over half of the events were from outpatient subspecialty care; fewer events occurred in home/community (5.2%), primary care (2.1%), or dialysis (2.0%) settings. Medication-related events were most common, followed by clinical deterioration and falls. Predictors of higher harm included diagnostic errors, patient/caregiver challenges, and events occurring in home/community or psychiatric settings. These results can help ambulatory care settings target safety events and develop systems-level prevention strategies.