Migration is a perennial part of human history, but while communications and transport technologies make it easier than ever for some, practical, material and legal barriers make it extremely difficult for many. In the context of ecological degradation and climate change, migration will become ever more urgent for ever greater numbers of people in the coming decades, even with mitigation and adaptation efforts. International Migrants Day is the United Nations' day to affirm acommitment to safe and dignified migration for all.