The core argument of this article is that pre-negotiation matters. Policy problems are not just out there , but socially constructed. In order to comprehend the outcome of any negotiation it is therefore not sufficient just to look at the give and take at the actual bargaining table, but also at the negotiation to negotiate . Furthermore, the article argues that pre-negotiation carves out a role for agenda-setting, seeing that governments often enter this phase with un-fixed preferences. These central points of the article are summed up in a theoretical framework, which stands out as a critique of liberal intergovernmentalism. On the basis of this framework the article sets out to analyse the pre-negotiation phase of eastern enlargement, the Luxembourg Summit. Its key conclusion is that the majority of the governments entered this game searching for their preferences and that this enabled both the Commission and two smaller states to influence the outcome by setting the agenda in a specific way.