The present study analyzes interregional migration flows in Finland during 1985-96 using a large sample from the longitudinal census data file. The regional concentration of population has sped up in recent years, and most migrants now head to five urban growth centers. The empirical analysis reveals that it is particularly the human capital component (young, educated individuals) that moves to, and stays in, the growth centers. They are attracted by the higher expected wages and employment chances. Conversely, some individuals, mainly older and less educated ones, move back to their original home regions. This countermovement reduces the speed of population concentration. Declining regions are nevertheless rapidly losing their most productive human capital through interregional migration flows.