International Organization

Research Article

In View of Ratification: Governmental Preferences and Domestic Constraints at the Amsterdam Intergovernmental Conference

Simon Hug and Thomas König


The bargaining product of the Amsterdam Intergovernmental Conference—the Amsterdam Treaty—dwindled down the draft proposal to a consensus set of all fifteen member states of the European Union (EU). Using the two-level concept of international bargains, we provide a thorough analysis of how this consensus set was reached by issue subtraction with respect to domestic ratification constraints. Drawing on data sets covering the positions of all negotiating actors and ratifying national political parties, we first highlight the differences in the Amsterdam ratification procedures in the fifteen member states of the EU. This analysis allows us to compare the varying ratification difficulties in each country. Second, our empirical analysis of the treaty negotiations shows that member states excluded half of the Amsterdam bargaining issues to secure a smooth ratification. Because member states with higher domestic ratification constraints performed better in eliminating uncomfortable issues at the Amsterdam Intergovernmental Conference, issue subtraction can be explained by the extent to which the negotiators were constrained by domestic interests.

Simon Hug is Assistant Professor at the Department of Government, University of Texas, Austin, Texas. He can be reached at

Thomas Koenig is Professor of Political Science at the University Konstanz, Germany and a Fulbright Distinguished Professor at Washington University, St. Louis, Missouri. He can be reached at