Infection control professionals play several important roles--surveyors, educators, and ultimately change agents--in the identification and prevention of nosocomial infections in hospitals. The medical and surgical intensive care units (ICUs) in a large inner-city teaching hospital experienced an increased patient colonization rate with vancomycin-resistant enterococcus (VRE). Intervening in this problem required a multifaceted approach to control the spread of VRE and to change behavior by shifting social norms at multiple levels throughout the ICU community. The success of the interventions could be best explained by applying the use of several behavioral science models. The Ecological Model of Behavior Change, the Health Belief Model, and Social Cognitive Theory can be applied and are consistent with the successful interventions. This multifaceted approach to intervening in this problem consists of five levels of influence: (1) intrapersonal or individual factors, (2) interpersonal factors, (3) institutional factors, (4) community factors, and (5) public factors. We implemented educational inservices and developed references, policies, and programs directed at each of the five levels of influence. The Health Belief Model and Social Cognitive Theory were employed for intervention, and behavior change was based on modeling, observational learning, and vicarious reinforcement. Within six months of initial implementation, the number of positive VRE surveillance cultures and positive clinical isolates decreased significantly in both the medical and surgical ICUs. Two years later, there continues to be a marked reduction of VRE.