The Brussels Convention on Jurisdiction and the Enforcement of Judgments in Civil and Commercial Matters1 contains an inflexible rule for dealing with the situation in which the same cause of action is being litigated in the courts of two or more Contracting States. Article 21 provides that the court seised first is entitled to hear the case but that all other courts must, of their own motion, decline jurisdiction in favour of the court seised first.2 Not wholly accurately, this has been called a rule of “first come, first served”. According to the jurisprudence of the Court of Justice of the European Communities, the question of whether, and how, a court is seised is a matter for the procedural law of that court. There are two supporting pillars for this latter conclusion. The first is the decision of the Court of Justice in Case