The welfare state is not merely a stand-in for missing markets; it can do a whole lot more. When generations overlap and the young must borrow to make educational investments, a dynamically-efficient welfare state, by taxing the middle-aged and offering a compensatory old-age pension, can...

We describe a "business as usual" (BAU) economy in which pollution is a by-product of productive activity by the current generation but "damages" production for future generations. Over time, conditions in the BAU economy become dire: it gets increasingly polluted, consumption falls and...

Many countries face the problem of how to reform social security systems to cope with increasing life expectancy. This raises questions concerning both distribution and risk sharing across generations. These issues are addressed within an OLG model with stochastic life expectancy across...