Questions concerning arbitral jurisdiction often arise. One such question is whether an arbitration agreement contained in one contract applies to disputes concerning other contracts. This thesis investigates and compares how the legal systems of Sweden, Switzerland and England - three distinguished international arbitration jurisdictions - have addressed the problem of arbitral jurisdiction in multi-contract relations. The thesis analyses three arbitral jurisdiction factors and places the multi-contract problem in its proper procedural law context. It also examines certain normative implications, such as the right of access to court, party autonomy, legal certainty, procedural economy as well as the advantages of arbitration. The comparison uncovers several important differences between the legal systems under analysis. At a macro level, the thesis finds that the three legal systems do show a liberal arbitration-friendly approach to the question of arbitral jurisdiction, towards which Swiss law and English law seem to have developed gradually, while Swedish law appears less consistent. Monica Seifert is a researcher and teacher in procedural law at Stockholm University and senior legal counsel at Kungl. Tekniska högskolan. She has a Master of Laws degree from Stockholm University and from Albert-Ludwigs-Universität Freiburg, Germany. Monica has previously worked at law firms in Sweden and Switzerland.