In this paper, the jurisdiction agreement is discussed as an important institute of international civil procedural law based on party autonomy. This institute is organized on three levels: national, European and international. At the national level - the level of the Croatian legal system - the most important for the agreement on jurisdiction is the Act on Private International Law, at the European level the Brussels I Regulation (recast), and at the international level the Convention on Choice of Court Agreements. In addition to the term, the legal nature of the agreement on jurisdiction, as well as its types (agreements on the choice of exclusively competent court, agreements on the choice of a court that is not exclusively competent, and asymmetric agreements) are explained. Within the jurisdiction agreement, there is a distinction between express and tacit jurisdiction agreement, often called express and tacit prorogation. Most of the work refers to express prorogation, which is considered a "real" agreement on jurisdiction. The express agreement on jurisdiction is addressed through legal sources, assumptions of validity and effects of the agreement on jurisdiction. Validity assumptions are divided into three groups: general, material and formal assumptions. Each of the assumptions is discussed in more detail in the paper. The effects, as well as the validity assumptions, can be divided into three groups: effects in relation to the prorogued court, effects in relation to other courts and effects in relation to contracting parties and third parties. After the express agreement on jurisdiction, a tacit agreement on jurisdiction was worked out. Thus, this work provides a rounded whole of the institute of jurisdiction agreements.