Despite the great promise that telehealth holds for improving cost, quality and access, there is currently a disjunction between what we know about telehealth and system growth and performance. To better understand the relationship between these two facets of telehealth development, this paper examines trends in telehealth, both as an intellectual endeavor and as a practical means of providing health services. Although there are promising avenues for government intervention in the way of coordination, funding, and regulatory practice, lack of knowledge regarding what works and what does not work has served as a major impediment to further progress in this area. In the absence of solid empirical evidence, key decision makers entertain doubts about telehealth's effectiveness, which, in turn, limits public leadership, private investment, and the long-term integration of telehealth into the health and technological mainstream. Solving the disjuncture between research and practice will require additional clinical trials and evaluation studies that examine the efficacy of various technologies, both relative to each other and to conventional in person medical encounters. At the same time, it will require more even distribution of research across applications, service locations, regions, and nations. But the generation of additional high-quality empirical data on process, benefits, costs, and effects is only the beginning. That data must in turn be used to effectuate change. This will require researchers to take a more proactive stance in promoting use of their findings, both instrumentally, to adjust, modify or improve particular programs or policies, and conceptually, to influence how key stakeholders think about telehealth more generally.