Migration
![Migration](https://demography.cass.anu.edu.au/sites/default/files/styles/anu_doublewide_680_220/public/image/migration.jpg?itok=bYFRBms_)
Populations are shaped by the interaction of the ever-changing processes of birth, death and migration. Demographic transition to low fertility and low mortality in industrialised populations is accompanied by population ageing. Migration may be viewed as a response to inequalities in ageing and socio-economic development with far-reaching policy implications.