The work is mainly concerned with how jurisdiction is allocated in private EC competition law disputes which have connections with more than one country.  The question when the English court is entitled to refuse recognition and enforcement of a foreign judgment, which misapplies or neglects EC competition law, is duly examined as well.  Much of the law which provides the framework for the resolution of such disputes is derived from international legal sources, as a consequence of which English law is very similar to or the same as the law of other countries in Europe. The thesis comprises four main parts.  The <i>first</i> part introduces the sources that are relevant for jurisdiction and judgments in relation to EC competition law claims.  The second part considers the potential jurisdiction problems in antitrust claims and specifies the bases upon which the English courts may exercise jurisdiction in private proceedings arising under EC competition law.  The thesis’ <i>third</i> part focuses on questions related to the jurisdiction of arbitral tribunals in EC competition law claims and the jurisdiction of English courts in proceedings ancillary to arbitration in relation to those claims.  The <i>fourth</i> part of the work is an analysis of the issue related to recognition and enforcement of foreign judgements in relation to EC competition law claims. The study shows that as a result of the decentralised enforcement of EC competition law, the private international law rules, related to jurisdiction and enforcement of foreign judgments, have a vital role to play if EC competition and law is to be enforced effectively and fulfil its economic function adequately.