Frans Willekens is Professor Emeritus of Population Studies, University of Groningen, the Netherlands, and former director of the Netherlands Interdisciplinary Demographic Institute (NIDI) in The Hague. He is now Honorary Fellow of NIDI. From April 2013 to March 2016, Frans Willekens was Senior Research Scientist and Chief Research Coordinator at the Max Planck Institute for Demographic Research (MPIDR) in Rostock, Germany. The principal focus of his research is international migration, in particular the simulation and agent-based modelling of international migration flows.