This paper investigates the determinants of the firm’s decisions to engage R&D cooperation,differentiating between if the cooperation is with national or internationalpartners. In our analysis we compare the six types of cooperation partners: cooperationwith competitors, suppliers or customers, and institutions from Spain, andcooperation with competitors, suppliers or customers, and institutions from acountry outside Spain, looking at whether is a foreign firm or domestic firm.  We use data from the Spanish TechnologicalInnovation Panel (PITEC) for the years 2005-2011. We apply a multivariateprobit model which allow for systematic correlations among the different choices.The results show that foreign firms are likely to cooperate with internationalsuppliers or customers. In contrast, foreign firms are less likely to cooperatewith national suppliers or customers, competitors and institutions, andinternational competitors and institutions. Through these results, we observethat to analyze what kind of partner companies cooperate, it is important todifferentiate between whether it is a national or international cooperation.