Đan Mạch trưng cầu dân ý Hiệp ước Maastricht

A referendum on the Maastricht Treaty for the founding of the European Union was held in Denmark on 2 June 1992. The treaty was rejected by 50.7% of voters with a turnout of 83.1%. This meant a serious hurdle on the way in the process of further European integration, which nevertheless did continue because all twelve member states did want to ratify.

The result of the referendum, along with the "petit oui" in the French Maastricht referendum did however signal a new stadium in European integration, away from the "permissive consensus" which had existed in most of the memberstates until then. Integration mainly did occur through strategic negotiations between the Member States or through functional adaptation of the system. Now the question of democracy as an explanatory variable had to be taken into consideration. This was expressed by Pascal Lamy, chef de cabinet for Jacques Delors, the president of the European Commission, who after the Danish referendum remarked that, "Europe was built in a Saint-Simonian [i.e., technocratic] way from the beginning, this was Monnet's approach: The people weren't ready to agree to integration, so you had to get on without telling them too much about what was happening. Now Saint-Simonianism is finished. It can't work when you have to face democratic opinion."

From this point forward issues relating to European integration were subject to deeper discussions across much of Europe. Some years later overt euroscepticism gained prominence. Besides Denmark only France and Ireland held referendums on the Maastricht Treaty ratification.

As the Maastricht Treaty could only come into effect if all members of the European Union ratified it, negotiations were set up in the months following the referendum. This resulted in the Edinburgh Agreement, providing Denmark with four exceptions or opt-outs from close co-operation in certain policy fields which eventually led to Denmark ratifying the Maastricht Treaty in a 1993 referendum.