This annual publication reflects recent efforts made by the OECD to improve the quality and availability of industrial R&D expenditure and researchers, scientists and engineers data. The publication presents estimated R&D expenditure data covering a period of 23 years for 15 OECD countries, as well as a zone total for the European Union. It then presents estimated R&D researchers, scientists and engineers data covering a period of 22 years for seven OECD countries. The greater international comparability of this data makes it invaluable for economic research and analysis.