What is the potential of new data sources, such as mobile phones, social media and satellite imagery, to improve understanding of international migration and human mobility? How could data from these sources complement data from traditional sources, such as national population censuses, surveys and administrative sources, and inform migration-related policies? These questions were discussed at an expert workshop co-organized by the European Commission Knowledge Centre on Migration and Demography (KCMD) and the International Organization for Migration (IOM) Global Migration Data Analysis Centre (GMDAC) in Ispra, Italy, on 30 November 2018. This Data Bulletin issue, co-authored with KCMD, provides a summary of the workshop outcomes.