A connection exists between enlargement of the European Union and reforms of the Common Agricultural Policy (CAP). Based upon rational choice theory, we examine whether the member states’ CAP positions are related to structures in their agricultural sectors. The overall hypothesis is that intensiveness of agricultural production corresponds to the willingness to reform the CAP. Political CAP positions, together with the development of member states’ structural fundamentals, are analysed using cluster analysis. The results show that EU enlargements have extensified agricultural production at the EU level, and that extensive agricultural production in a member state is often an indicator of reduced willingness to reform. However, the intensiveness of agricultural production is only part of the explanation. Moreover, negotiation tactics play an important role for the positions on the CAP.