This study examines a naturally occurring experiment in a large urban hospital faced with budget cuts, in which departments were ordered to reduce employees' overtime without jeopardizing service quality. The study focuses on two departments that chose to use behavior modification techniques. In one department (Radiology) the intervention combined behavior modification techniques with participatory management, while the second (Emergency Room) used only behavior modification techniques. Both interventions focused on the behavior of supervisory staff responsible for assigning overtime. Analysis of the departments suggested that they were generally comparable in staffing and in demands for overtime use. An interrupted time-series analysis was employed to measure trends in overtime usage before and after the introduction of the interventions. Results indicate that a combination of participatory management and behavior modification techniques led to a more efficient reduction in overtime than did behavior modification techniques used alone. (Author/TE)