Résumé : The aim of the paper is to explore which factors explain the reasons for firms’ decisions to delocalize their R&D activities outside or within the EU. Special attention is given to the influence of public policies to support R&D on the decisions to (de)localize R&D activities. The main source of information is “The EU survey on R&D Investment Business Trends” for the years 2007-2013. The methodology is based on a descriptive analysis of these surveys, on benchmarking with other economic studies in the field and a SWOT analysis of R&D activity location in the EU. The analysis reveals that the quality of R&D personnel and access to network knowledge (with firms, universities and public organizations) are the most important factors for locating R&D activities in a given region or country. Public support for R&D appears to be relegated to a secondary position in the decision to locate R&D activities.