LL.M. (International Commercial Law) / The main exploration of this paper is whether a breach of contract as a ground for jurisdiction is sufficient for a court in England or South Africa to exercise jurisdiction. This question seems straightforward in England, but not so much in South Africa. England enacted their Civil Procedure Rules to make provision for a court to exercise jurisdiction when a plaintiff who is in England wants to sue a foreign defendant in England.1 The breach of contract must occur in the jurisdiction before an English court will permit service out of the jurisdiction. South Africa’s laws on jurisdiction are derived from Roman law.2 A foreign peregrinus may sue in South Africa either where the incola is domiciled or resident or where the cause of action arises. Breach of contract is allowed in this circumstance. It is necessary for an incola plaintiff to attach property of a foreign peregrinus defendant when he wants to sue the foreign peregrinus in a South African court. This may be done where the attachment founds jurisdiction of the court, ie where the incola sues in the area where he is domiciled or resides, or where the attachment confirms the jurisdiction of the court, ie where the cause of action arises. The cause of action in relation to contracts includes the conclusion of the contract or the performance of the contract in the jurisdiction if the plaintiff sues where the cause of action arises and not where the plaintiff is domiciled or resident. The matter of whether a breach of contract can be regarded as a ratio jurisdictionis is seldom approached by South African courts. In Natal, courts allowed attachment of the defendant’s properties where there were no rationes jurisdictionis...