PROJECT SUMMARY In select patients, early reperfusion for acute stroke saves lives and reduces disability. The question is how to ensure that reperfusion is provided to all eligible patients. Larger hospitals typically have on-call stroke teams that quickly assess patients with suspected stroke and determine eligibility. Unfortunately, most smaller, rural hospitals do not have this expertise readily at hand and therefore stroke patients seen at these hospitals may not receive these critical interventions and optimal care. Telestroke is a potential solution. In telestroke a stroke expert who is physically far away uses technology and videoconferencing to help evaluate the patient. Availability of telestroke in emergency departments and hospitals is increasing across the nation. The hope is that telestroke will increase rates of reperfusion, decrease disability and mortality, and lead to regionalization of stroke care - most patients receive care near their home while the critically ill are efficiently transferred to specialized centers. There is limited quantitative data on the impact of telestroke on these outcomes. In this proposed mixed-methods study we use national data from approximately 50 million adults where we match stroke patients at 767 hospitals with telestroke to similar patients at similar hospitals without telestroke to quantify telestroke's larger impact on patterns of care (Aim 1) as well as reperfusion, mortality, and longer-term disability (Aim 2). We complement this with qualitative analyses on the impact of telestroke from the perspective of front-line providers and barriers and facilitators to effective use (Aim 3). The proposed study will be the largest and most comprehensive study on telestroke to date. Our hope is that the findings will inform more evidence-based policy and clinical decisions on telestroke and where patients with acute stroke receive care.