The aim of this graduate paper is to present an overview of the concession institute with a focus on the maritime domain concession in the Croatian legal system. The concession institute is governed by the 2017 Concession Act, but the details of this institute are governed by many specific regulations, depending on the subject matter and activity of the concession. The maritime domain concession is governed by the Act on maritime goods and seaports of 2003. With this law, concession on maritime good is regulated as a right to exclude maritime good from the general use and to allow special use or economic use to natural and legal persons, resulting from a concession decision taken by a public authority (Government of the Republic of Croatia or the competent authority of regional or local self-government). The right shall be specified in a contract concluded by the grantor with the selected tenderer who satisfies the conditions for the concessionaire. The first part of this graduate paper is about the concession institute itself, its characteristics and the concept of maritime goods. The main focus is to be placed on the maritime domain concession, on the participants in the legal relationship, the concession award procedure depending on the type of concession to be given, the decision and the concession agreement, the disposal of the concession holder and the legal protection.