‘Jurisdiction’ means the competence of the courts to hear and decide a case. For the purpose of determining the jurisdiction of the English courts, actions are of two kinds.

1. (i) Actions in personam: these are actions brought to compel a defendant to do or to refrain from doing something or to pay damages. Jurisdiction over such actions depends primarily, though not exclusively, on the defendant's presence in England. This chapter is mainly concerned with actions in personam.

2. (ii) Actions in rem: these are actions against ships and aircraft when jurisdiction depends upon the presence of the ship or aircraft in England.

It should be added that, in some cases, such as divorce or nullity of marriage, sometimes called ‘actions quasi in rem’ since they involve determination of personal status, jurisdiction is entirely statutory. These are dealt with separately.

Jurisdiction in actions in personam

In such actions, including actions in contract and tort and those respecting property other than ships and aircraft, jurisdiction may, in cases where the defendant is not present in England when the action is started, be acquired if the defendant submits to the jurisdiction and, in some situations, where the court allows him to be served with a claim form.