This paper describes the methods used to classify the OECD countries' industrial sectors and manufactures by level of technology, and presents the resulting classifications. In the proposed new classification by industrial sector, the concept of technology intensity has been expanded to take into account both the level of technology specific to the sector (measured by the ratio of R&D expenditure to value added) and the technology embodied in purchases of intermediate and capital goods. Four groups of industries have been identified on the basis of the degree of technology intensity. The classification by product consists solely of high-technology products (products which are the most technology-intensive). The classification was drawn up by the OECD Secretariat in collaboration with Eurostat, the object being to finalise the approach by sector and provide a more appropriate instrument for analysing international trade. Because no detailed data were available for services, the two proposed classifications concern only manufacturing industry. The sectoral approach involves identifying the technology content of an industry and using R&D intensity as the main criterion. The classification by product focuses on high-technology products and uses the Standard International Trade Classification. The paper discusses the methods used to calculate R&D intensity, including direct and indirect intensity, and the challenges in determining technology intensity. The classifications are based on data from the International Standard Industrial Classification and the Standard International Trade Classification. The paper also highlights the limitations of the classifications, including the lack of detailed data and the difficulty in accurately measuring technology intensity. The classifications are intended to provide a more accurate and consistent way of analysing international trade and technology.This paper describes the methods used to classify the OECD countries' industrial sectors and manufactures by level of technology, and presents the resulting classifications. In the proposed new classification by industrial sector, the concept of technology intensity has been expanded to take into account both the level of technology specific to the sector (measured by the ratio of R&D expenditure to value added) and the technology embodied in purchases of intermediate and capital goods. Four groups of industries have been identified on the basis of the degree of technology intensity. The classification by product consists solely of high-technology products (products which are the most technology-intensive). The classification was drawn up by the OECD Secretariat in collaboration with Eurostat, the object being to finalise the approach by sector and provide a more appropriate instrument for analysing international trade. Because no detailed data were available for services, the two proposed classifications concern only manufacturing industry. The sectoral approach involves identifying the technology content of an industry and using R&D intensity as the main criterion. The classification by product focuses on high-technology products and uses the Standard International Trade Classification. The paper discusses the methods used to calculate R&D intensity, including direct and indirect intensity, and the challenges in determining technology intensity. The classifications are based on data from the International Standard Industrial Classification and the Standard International Trade Classification. The paper also highlights the limitations of the classifications, including the lack of detailed data and the difficulty in accurately measuring technology intensity. The classifications are intended to provide a more accurate and consistent way of analysing international trade and technology.