Agricultural producers may use collective action to achieve common interests related to their agricultural activities. Such cooperation might range from the planning of production to placing products on the market. Producer organisations (POs) often also sell products of their members and perform activities such as e.g. joint purchase of inputs, storage, transport and logistics, quality control but also many other activities. The Common Agricultural Policy (CAP) actively promotes organisations among agricultural producers and considers collective action an important self-help tool for strengthening the positions of farmers in the food supply chain. Regulation (EU) No 1308/2013 (Common Market Organisation - CMO Regulation) expressly recognises the added value of horizontal cooperation at primary production level when it states that “producer organisations and their associations can play useful roles in concentrating supply, in improving the marketing, planning and adjusting of production to demand, optimising production costs and stabilising producer prices, carrying out research, promoting best practices and providing technical assistance, managing by-products and risk management tools available to their members, thereby contributing to strengthening the position of producers in the food supply chain”. Therefore, the CMO Regulation establishes rules for the recognition of producer organisations (recognised POs) and associations of producer organisations (recognised APOs). Recognised POs/APOs can obtain certain start-up funding under the rural development rules or financing via operational funds in the fruit and vegetable (FV) sector, and they can profit from certain derogations from EU competition rules. Previous EU-wide studies that have been conducted in this area fall short of providing a general overview of the number, legal forms and type of activities carried out under horizontal cooperation arrangements, which European farmers resort to today. In addition, the functioning of POs/APOs as well as the incentives and disincentives of producers to create POs and the impact that POs have on their members and on the food supply chain has not been described in detail in the majority of EU Member States. Against this background and based on a European Parliament initiative, the Directorate-General for Agriculture and Rural Development (DG AGRI) of the European Commission commissioned an “analysis of the best ways for producer organisations to be formed, carry out their activities and be supported” that started in December 2017 for a duration of 15 months.