This paper provides a new taxonomy of industries according to their level of R&D intensity - the ratio of R&D to value added within an industry. Manufacturing and non-manufacturing activities are clustered into five groups (high, medium-high, medium, medium-low, and low R&D intensity industries), drawing on new and expanded evidence from most OECD countries and some partner economies. This paper also reports on differences in R&D intensity within industries across countries. This document represents an update and reframing of previous OECD taxonomies based on earlier versions of the International Standard Industrial Classification (ISIC), including services, whose coverage has improved in the R&D tables published by OECD (ANBERD). This taxonomy aims to support the presentation of statistics for industry groups when R&D is a relevant discriminant factor. Other existing or in-development taxonomies may be more appropriate for capturing differences in overall knowledge intensity or technology use.