A recent AHRQ technical brief on ambulatory safety found that evidence for effective interventions is lacking. This cluster-randomized controlled trial examined whether participation in a multimodal quality improvement intervention enhanced safety processes at primary care clinics compared to usual practice. Using chart review, investigators determined that clinics receiving the intervention—which included a learning network, webinars, in-person meetings, and coaching—improved documentation and patient notification for abnormal test results overall. Also, time between test date and treatment plan was shorter in intervention sites. Through pre–post surveys, they learned that patient perceptions of quality and safety improved modestly for coordination and communication but were otherwise similar between the sites. Staff perceptions of safety and quality were similar pre–post and between intervention and control sites. Barriers to improvement included time and resource constraints, staff turnover, health information technology, and local practice variation. The authors recommend further study to determine the potential for multimodal practice-level interventions to enhance outpatient safety.