For hundreds of thousands of years our ability – and willingness – to move over vast distances has allowed humans to escape existential threats and thrive as a species. Yet human mobility today faces ever stronger barriers that not only harm the lives of potential migrants, but also threaten our own societies. The migration impulse is a core facet of the human condition: in attempting to suppress it, governments are sacrificing the future of humanity for the sake of short-term political gain. Visionary thinker Ian Goldin tells the millennia-spanning story of the movement of peoples, offering a powerful set of tools to understand the present as well as the past. Goldin is Oxford Professor of Globalisation and Development. His books include Terra Incognita, Age of Discovery and Age of the City.