Research into environmental migration or, as the authors phrase it, “people movement in the context of environmental change” has focused on understanding the phenomenon itself. However, it is timely to take a less-travelled route and instead study the experts focusing on environmental migration. This brief reports on an online questionnaire of 262 such experts, situating their perceptions of environmental migration within the policy development they help to drive, directly or indirectly. Such a study is important because policy does not develop solely on the basis of objective assessments of the world “out there”. Policy is also influenced by the knowledges, values, beliefs, assumptions, cultural contexts and activities of people involved in its development. At a milestone moment when, after a long period of research and debate, environmental migration is being formalized on policy agendas, one can ask: What are the characteristics of experts? How do they define environmental migration, and what policies do they support? Knowing the answers to these questions can aid policy formation and, importantly, evaluation of policies and programmes addressing environmental migration, as well as self-eval