The purpose of this paper is to analyze foreign direct investment (FDI) flows in Spain at regional and sectoral levels over the period 1997-2013. After showing that they are very volatile and highly geographically concentrated, the paper examines their determinants by estimating an FDI equation by GMM and GLS. This is done not only for the whole period and total FDI but also for two sub-periods (pre-crisis and crisis) and main places of origin (Europe and America). The results show that FDI inflows in Spain are mainly determined by market size, the level of human capital in interaction with wages, and the own characteristics of Madrid.