This paper develops a simple analytical framework in which optimal health and retirement policies amid population aging can be discussed. To be efficient, these policies must recognize and exploit the dynamic complementarities between the timing of retirement, the size of lifecycle labour income and pension payments and investments in health that individuals make, for example, by purchasing medical care and that society makes by advancing medical technology. We aim to show how the traditionally separate areas of health and retirement policy can be coordinated to achieve dynamic efficiency. Under fairly general assumptions, postponing the age of retirement and greater health spending are shown to be complements in the maximization of lifecycle utility. Mandatory retirement and pension policies that change the constraints workers face can be used to induce voluntary health investments by individuals and improve society's incentives to adopt new medical technology. Leaving a hitherto optimal mandatory retirement age unchanged as new medical technologies improve the efficacy of healthcare would be inefficient. The aggregate ability and willingness to pay for medical care and technology will be greater, the higher an economy's per capita income, suggesting large welfare gains from postponing the average age of retirement if investments in new medical technology target the quality of life and raise the productivity of people working past a long-established mandatory retirement age.