Migration, both within and beyond borders, has become an increasingly prominent theme in domestic and international debates, and is the topic of the 2009 Human Development Report (HDR09). The starting point is that the global distribution of capabilities is extraordinarily unequal, and that this is a major driver for movement of people. Migration can expand their choices —in terms of incomes, accessing services and participation, for example— but the opportunities open to people vary from those who are best endowed to those with limited skills and assets. These underlying inequalities, which can be compounded by policy distortions, is a theme of the report.