Using panel data from the Spanish Ministry of Science and Technology from 1999 to 2007, this paper is the first to analyze the relationship between ownership structure and the Human Resources strategy in Spain. One of our key findings is that two stable HR strategy equilibria exist: a high commitment strategy, with firms, paying higher wages and spending more on training than their competitors, and a low commitment strategy. We find that corporate and foreign blockholders increase the probability that firms follow a high commitment HR strategy, while family ownership, if combined with family management is negatively related to the choice of a high commitment strategy. However, we find that blockholders may mitigate this negative effect by giving family firms access to new technologies and strategies. Our results show that a high commitment HR strategy is desirable for most firms, since it leads to higher productivity and profitability in the long run. However, some firms may prefer a low commitment strategy, if it is more consistent with the firm's overall strategy.