The African, Caribbean, and Pacific (ACP) Group of States is an intergovernmental organization established by the Georgetown Agreement in June 1975, and it consists of 79 countries across three continents. This heterogeneous cluster of countries, originally bound by their colonial ties with the member states of the European Union (EU), came together out of the need to form a common front in the negotiations of the first ACP–EU partnership. The spirit of the Lomé Convention (1975–2000), initially considered a very progressive model of North–South cooperation, gradually evaporated; thus, the Cotonou Agreement (2000–2020), with its profound changes in the areas of aid and trade, was an attempt to normalize relations between the two blocs. The overall patchy record of the various ACP–EU partnership agreements and a number of events—notably, decreased interest within the EU, intensification of regionalization dynamics in the ACP Group, and adoption of separate strategies for cooperation with African, Caribbean, and Pacific countries and regions—cast doubts upon the relevance of the ACP–EU framework and threatened the existence of the ACP Group. Unsurprisingly, the launch of the negotiations in September 2018 for a new ACP–EU partnership was not without difficulty. While there are no doubts that the ACP Group has intrinsically been linked to the EU, at the same time it should be noted that it has attempted to promote intra-ACP cooperation, although with mixed successes at best, and to strengthen its presence in the international arena and diversify its partnerships, also in this case with limited results. Indeed, despite various pledges to support the principles of unity and solidarity, the effectiveness of the ACP Group has been compromised by the interplay of a plurality of interests, limited financial resources, and a perceived delinkage of the Brussels-based institutions from ACP national capitals. The revision of the Georgetown Agreement in December 2019, including the transformation into the Organisation of the African, Caribbean and Pacific States (OACPS), is an attempt to reinvigorate the ACP Group, with stronger emphasis on financial sustainability, joint action for the pursuit of multilateralism, and, importantly, increased autonomy from the EU.