Telehealth is defined as the use of telecommunication and information technologies to provide health care services at a distance. Telehealth modalities include mobile health, remote monitoring, store-and-forward, and videoconferencing. Telehealth supports a range of activities including: direct patient-to-provider interaction; monitoring patient health and activities; interactions among providers to improve patient care; and use by hospitals to enhance service capacity and quality.  This presentation will focus on telehealth applications in emergency departments, describing research findings on how it is used and the effects of its use for patients, providers, and health systems.