The book by the International Organization for Migration (IOM) and Eurasylum on ’Assessing the Costs and Impacts of Migration Policy: an International Comparison’ has just been published. The book explores some of the key issues, at a policy and practical level, relating to the design, implementation and outcomes of public evaluation systems in the field of migration policy. It reviews the ways migration policies are evaluated in several EU member states, the USA, Canada, the European Commission, IOM and UNHCR, and provides a range of recommendations for improving the design and implementation of evidence-based and accountable policies in the field of migration and asylum.