This paper studies optimal intergenerational transfer policy under stochastic labor income and capital returns. It has implications for Social Security, government tax and debt policy, and DB pension funds. A stylized two-period overlapping-generations model is developed where a central planner implements pay-as-you-go transfers. I allow for autocorrelation in the labor income and skewness in the capital return and calibrate the model parameters to US data. I show that state-contingent transfers facilitate intergenerational risk sharing in a way that is similar to portfolio insurance using put options. That is, the working generation provides downside risk insurance to the old on their savings. In addition, when no riskfree asset is available, these transfers improve utility by substituting for this missing asset. I further find that imposing an incentive constraint for the working generation has little impact when transfers also have this substitution role, but it causes the transfer scheme to collapse to the zero-transfer scheme when a risk free asset is available.
