This edited collection includes (but is not limited to) contributions in the form of chapters from the participants of the Workshop on the Macroeconomics of Migration at the University of Sheffield in June 2018. Migration is one of the most debated issues currently and is a pervasive feature of our economies. While extensive academic work has looked at the microeconomic aspects of migration, an open question is to better understand the links between migration and macroeconomic aggregates, such as per capita GDP. This book explores this overarching question, which has hit the key political and social debates all over Europe. Countries that are traditionally viewed as hosting economies for immigrants, such as for instance the UK and Germany, are concerned by immigration, while sending countries, such as Southern and Eastern European countries, are concerned by emigration. The contributions in this edited collection analyse empirically and theoretically the challenges international economic migration generates both in sending and receiving countries, thus offering a comprehensive approach to the question asked above. The book looks at several important issues in the current debates related to the labour market effects of migration for natives, the bi-directional relation between taxation and migration, migration and the informal economy, migration and business cycle dynamics, and brain waste. This edited collection will be of interest to academics, practitioners and policy makers who wish to take a closer look at the macroeconomic effects of migration and learn more about the current challenges posed by immigration in some countries and emigration in others.