This article poses three questions about the recent resurgence of academic and policy interest in migration, development and diasporas. First, over many years the connection between migration and development has been of marginal interest for many of those involved in the field of development studies; in many cases, where it has been considered, migration has been seen as a symptom of a development failure and cause of further underdevelopment. What has changed to bring about the dramatic turnaround in views in the last decade? Second, governments and development organisations are increasingly focusing on the role of ‘diasporas’ in the process of development. The attempts to co-opt diasporas into existing development practice tend to assume that they share a common set of interests and aspirations with the development industry.Here, we ask who is included within these diasporas and why should they be expected to contribute to development? This leads to the third question: what is the nature of development in which we are anticipating that the migration process and diasporas should play a role? This article argues that existing models of development are inherently sedentary and struggle to incorporate migration. In the increasingly mobile world new concepts of development are required. An open and critical dialogue between diaspora members and the development industry may help to achieve this.