This publication explains how the EU competition rules apply to various forms of horizontal cooperation. It considers information exchange between businesses, agreements relating to research and development (including an analysis of the European Commission’s R&D block exemption), and agreements relating to the production of goods or provision of services (including those covered by the Commission’s specialisation block exemption). It also covers other forms of horizontal cooperation at different stages in the business development, production and supply chain - notably purchasing agreements concerning raw materials and inputs, commercialisation agreements relating to sales and marketing, and standardisation agreements.