Abstract
Demographic projections stress the increasing gap between the population growth in LDCs' and in MDCs', where the prospects of recovery numerical and aging are likely to alter the equilibrium of welfare. In next decades, the old Europe and the young Africa will increasingly be required to seek a common strategy to solve the problems of a demographic change that, on the one hand, has gone far beyond the mythical goal of zero growth, on the other hand, has triggered a phase of rapid population growth addressed to continue for at least another half a century.
Since statistics show that any compensation between demographic surplus and deficit will be actually impossible, international migration from the South to the North to be functional should be transformed from the traditional "safety valve" into a "driver of the development ", through projects of circular migration involving the accumulation of knowledge, experience and financial resources to be transferred to the countries of origin in order to create development locally.