In this paper, different knowledge indicators are used to explain the GDP per capita growth of EU developed regions. Their impact is estimated by controlling for the initial level of GDP, the structural features of the regions and the spatial dependence. The main finding is that regional growth is positively and significantly affected by both the intensity of R&D and the share of adults with tertiary education. This result is robust to alternative estimation procedures, arising from both an OLS regression with country demeaned variables and two ML regressions for, respectively, a spatial error and a spatial lag model.