The right to health is often seen as being in enduring ‘crisis.’ On the one hand, social rights supporters see the pervasiveness of unsatisfied health needs as evidence of widespread violations of the right. On the other hand, social rights sceptics see the resource-conditional nature of the right as reason for its unenforceability. As a result, there is no tangible sense of where along the line between promising everything and delivering nothing the obligation to fulfil the right to health sits. This thesis suggests, however, that the right to health can be rescued. But the rescuer will require multi-disciplinary tools. The contribution made by this thesis is the development of a methodological framework for measuring right to health compliance. The contribution is two-fold. Firstly, through a public health-devised measurement of avoidable mortality, the thesis provides a methodology for describing what type of health the right to health guarantees. And secondly, through an econometric estimation of efficiency, it provides a methodology for determining what level of this type of health the right guarantees for individuals under resource scarcity as well as for offering a signal with respect to the degree to which this standard is in fact being met. It is argued that compliance with the obligation to fulfil the right to health is a function of the duty-bearer’s ability and willingness to provide for health. The results suggest that not all unmet health needs signal a violation of the right to health. Some duty-bearers are doing as well as they can with the maximum resources available, notwithstanding the relatively low levels of health sometimes being achieved. At the same time, the results also reveal many instances where the actual level of health achieved falls well short of the level expected. But, on the basis of the willingness indicators used in this thesis, whether these shortfalls systematically characterise unwillingness is unclear. Instead, this question requires a more nuanced, qualitative, investigation. In the case of Brazil, the hypothesis of unwillingness appears to hold. The methodology can be used efficiently for signalling compliance.