OBJECTIVES: Drowning is the second leading cause of unintentional death for American children in middle childhood, but behavioral research designed to prevent pediatric drowning is limited. This study tested the efficacy of a brief intervention to improve lifeguard attention and surveillance at a public swimming pool. METHOD: Observational data on patron risk-taking and lifeguard attention, distraction, and scanning were collected at a public swimming pool, both before and after a brief intervention. The intervention was designed to increase lifeguards' perception of susceptibility of drowning incidents, educate about potential severity of drowning, and help overcome perceived barriers about scanning the pool. RESULTS: Postintervention, lifeguards displayed better attention and scanning and patrons displayed less risky behavior. Change was maintained for the remainder of the season. CONCLUSION: Theoretically driven brief interventions targeting lifeguard attention and surveillance might prove effective in reducing risk of drowning in public swimming pools.