Insights into the past Energy Research and Technology Development (ERTD) expenditures allows policy makers to better set priorities for current and future ERTD funding as well as to analyze the exact impact of ERTD investments to the development of energy technologies. However, despite numerous attempts in the past, there is currently no comprehensive, validated database that includes disaggregated data on public and private ERTD expenditures in the EU-27 for different technology groups. One of the main aims of the Scientific Reference System for New Energy Technologies and Energy End Use Efficiency (SRS NET & EEE) FP6 project is to enhance the availability, quality and completeness of data on public and private ERTD expenditures, disaggregated for energy technologies and energy end-use efficiency options in the EU-27. The aim of the paper is to outline the main data gathering procedures and results from the "SRS NET & EEE" project, as well as the related policy implication. (C) 2008 Elsevier Ltd. All rights reserved