Flexible retirement – that is, the opportunity to choose one's own personal retirement age – is a hedge against pension risk and provides insurance to workers facing health or productivity shocks. Flexible retirement and flexible pension schemes are in practice closely linked because of imperfect capital markets and institutional restrictions. I discuss three necessary conditions to provide insurance through flexible retirement. First, it should be possible to adjust the pension starting date at limited cost. This condition is gradually being fulfilled, as many countries are moving toward more actuarially neutral pension schemes. Second, individuals should be willing to adjust their labor supply in case of a wealth shock. This condition seems largely fulfilled, although the available empirical evidence suggests that the ‘standard retirement age’ is at least as important as the income effect. Third, the labor market should be able to deal with flexible individual retirement decisions. This condition is gaining importance, but has not yet received much attention in the literature. Institutions often hamper employment past the ‘standard retirement age’. Moreover, the hiring rates of older workers are low and their unemployment duration is high. Institutional reforms facilitating flexible retirement opportunities are desirable from an insurance perspective.