Article 23 Council Regulation (EC) No 44/2001 (Brussels I)

1. If the parties, one or more of whom is domiciled in a Member State, have agreed that a court or the courts of a Member State are to have jurisdiction to settle any disputes which have arisen or which may arise in connection with a particular legal relationship, that court or those courts shall have jurisdiction. Such jurisdiction shall be exclusive unless the parties have agreed otherwise. Such an agreement conferring jurisdiction shall be either:
(a) in writing or evidenced in writing; or
(b) in a form which accords with practices which the parties have established between themselves; or
(c) in international trade or commerce, in a form which accords with a usage of which the parties are or ought to have been aware and which in such trade or commerce is widely known to, and regularly observed by, parties to contracts of the type involved in the particular trade or commerce concerned.

2. Any communication by electronic means which provides a durable record of the agreement shall be equivalent to "writing".

3. Where such an agreement is concluded by parties, none of whom is domiciled in a Member State, the courts of other Member States shall have no jurisdiction over their disputes unless the court or courts chosen have declined jurisdiction.

4. The court or courts of a Member State on which a trust instrument has conferred jurisdiction shall have exclusive jurisdiction in any proceedings brought against a settlor, trustee or beneficiary, if relations between these persons or their rights or obligations under the trust are involved.

5. Agreements or provisions of a trust instrument conferring jurisdiction shall have no legal force if they are contrary to Articles 13, 17 or 21, or if the courts whose jurisdiction they purport to exclude have exclusive jurisdiction by virtue of Article 22.