South–South migration has emerged as an important research and policy issue as global and regional debates about the relationship between migration and development have intensified. In the global South, skilled labour migration and knowledge transfer by and between members of diasporas are usually discussed in the context of South–North migration and have rarely been explored in the South–South context. However, research on South–South diaspora engagement is currently very limited and confined to small numbers of case studies. Using data from the United Nations Department of Economic and Social Affairs (UNDESA) bilateral migration database, this chapter shows that for many countries in the South, South–South migration is greater than South–North flows. The chapter reviews the state of knowledge on South–South migration and concludes by highlighting some of the important areas related to the role of South–South migration in the development of many countries in the global South.