This paper develops a taxonomy of 151 industries, mainly defined at the 3-digit level, indicating at which geographical level competition takes place. It classifies 40 industries as competing at the domestic level, 85 at the European level, and 26 at the global level. First, this paper creates a novel dataset that combines production and international trade data for both goods and services industries, defined at a detailed level of industry aggregation for 15 European countries (based on data availability). Then, by comparing domestic sales with international trade flows, and their source/destination, it identifies the geographic level of competition of each industry. The proposed classification can be used in numerous applications, from the design of trade policies to the assessment of competition by antitrust authorities. The paper shows that the taxonomy is broadly consistent with external data sources that provide alternative ways of inferring the degree of internationalisation of each industry.