A stream of recent judgments by the Grand Chamber of the European Court of Justice has shed light on the procedures that govern treaty-making by the European Union. This article explores how this case law approaches the principle of institutional balance and the duty of cooperation between the institutions. It argues that the former is construed in a balanced manner on the basis of a literal interpretation of primary law that promotes strict compliance with procedural rules and does not favour a particular institution. As for the duty of cooperation, whilst its procedural dimension is strengthened, its scope remains somewhat elusive. The analysis identifies a pragmatic streak in the Court's balanced approach, and argues that there is an inherent limit to the impact of constitutional law on inter-institutional disputes. Ultimately, the less time and energy the institutions waste on turf wars about their procedural powers, the greater their contribution to inceasing the efficiency of the Union's treaty-making practice.
