The contribution of migrants to receiving countries is a controversial issue. Statistics on the demographic contribution of migration can be presented from different perspectives on flows or stocks, taking into account first generation of immigrants or also their children. These figures reflect different time perspective on the contribution of migration to population growth and age structure. In terms of demographic growth, migration is in balance with the baby boom and increased life expectancy, and the effects of these two phenomena are often overlooked. In the case of France, from 1946 to 2014, international migration contributed to approximately one third of population growth.

Can migration counterbalance the effects of population ageing in terms of labour needs? Although the utilitarian case for immigration commonly argues the capacity of migrants to counter population ageing, labour migration can only play a limited (as in many longstanding immigration countries family and humanitarian migration are relatively much more important) and a temporary role (as migrants age).

The history of migration over the three last centuries reveals a permanent tension between two extreme visions: migration restricted to work migration adjusted to shortterm economic needs, versus settlement migration. The main challenge for migration policy is to find a form that conciliates both.