Physical inactivity is a recognized independent risk factor for the development of cardiovascular disease. However, a large proportion of the U.S. population does not participate in regular physical activity, and research has shown that without intervention, most people remain sedentary. Thus, an urgent need exists for developing effective interventions to promote physical-activity adoption and maintenance. Additionally, it is important that these interventions can be disseminated to the large population of sedentary individuals. To be disseminable, physical-activity interventions must move beyond reliance on strictly face-to-face modes and begin to more fully use newer technologies, such as the Internet. This article summarizes the progress made in promoting physical activity with interactive communications. We also delineate areas for future research.