We examine optimal taxation and social insurance if insurance markets are imperfect. This requires the development of a theory of labor supply under uncertainty. We show that the case for social insurance is not generally reinforced by adverse selection in insurance markets as social insurance...

We examine equilibria in competitive insurance markets when individuals take unobservable labor supply decisions. Precautionary labor motives intro-duce countervailing incentives in the insurance market, and equilibria with positive profits can occur even in the standard case in which...