The article discusses the impact of human capital migration upon the sustainable development of socio-economic systems. The authors compare advantages and costs of human capital migration based on the European migration crisis of 2015, distinguish migration consequences for receiving and donor-countries, analyze qualitative and quantitative features of human capital migration, discuss the impact produced by migration upon social expenses of the countries in the European Union and define the role of state social politics to resolve existing problems. The article shows that on the one hand, migration inflow creates additional stress for the system of social protection, and on the other, that countries receiving major migration flows exhibit a fairly high degree of socio-economic sustainability, and should thus compete for quality human capital.