Lyme disease is endemic to the Assateague Island area. Using a questionnaire and serosurvey, we examined the extent of tick exposure, compliance with recommended Lyme disease personal preventive activities, and risk of the disease in 86 outdoor workers on Assateague Island before and after the summer of 1989. Despite high self-reported tick exposure and relatively long employment durations on the island, there was no evidence of current or past infection with Borrelia burgdorferi, the causative agent of Lyme disease. Lyme disease knowledge and use of several personal strategies were high, but compliance with these preventive strategies was not universal. These data suggest that even in this high-risk population, intensive educational efforts are necessary to encourage Lyme disease preventive behavior, but the current level of compliance may have decreased the risk of Lyme disease on the island.