Despite substantial investment over recent years in telehealth there appears to be little consensus regarding what a successful implementation should achieve. However, defining success is often controversial and complex due to differing views from the large number of stakeholders involved, the local environment where telehealth is deployed and the scope, or size, of any planned initiative. Nevertheless, a number of generic measures are proposed in this paper which then provides a framework for the measurement of success. The local context can then be applied to determine the exact emphasis on specific measures, but it is proposed that all of the measures should be included in the holistic measurement of success. Having considered what constitutes success attention is then given to how success should be quantified. Robust evaluation is fundamental and there is much debate as to whether the �gold standard� Randomised Control Trial (RCT) is the most appropriate methodology for telehealth. If the intervention, technology and system, can be maintained in a stable state then the RCT may well provide the most authoritative evidence for decision makers. However, ensuring such stability, in what is still a novel combination of technology and service, is difficult and consequently other approaches may be more appropriate when stability is unlikely to be maintained
