The pay-as-you-go social security system, which suffers from dwindling labor force, can benefit from immigrants with birth rates that exceed the native-born birth rates in the host country. Thus, a social security system provides effectively an incentive to liberalize migration policy. The paper...

In the political debate people express the idea that immigrants are good because they can help pay for the old. The paper explores this idea in a dynamic political-economy setup. For this purpose we develop an OLG political economy model of social security and migration. We characterize sub-game...