Maritime domain is the most valuable natural resource of Repubilc of Croatia and lot of its untouched potential can still be profitably used. At the very begining of this thesis clearly is showed historical maritime domain`s regulation which started at Austro-Hungarian monarchy. Present definition and scope is defined by Maritime domain`s and sea ports Law that came into force at 2003. This law is still not harmonized with Concession`s Law and excatly this is gratest step to legal protection of maritime domain. Maritime domain`s management within coastal zone management is criterion of maintenance, advancement and concern about protection to prevent contamination, pollution, devastation by construction or breach of concession rights. Concessions toward maritime domain area can be divided into concessions in ports and concessions outside the port. Concessions for special usage of maritime domain are mostly granting for usage outside the port, while concessions for economic exploitation are granted in both port and outside the port area. To establish concession`s obligation there are two legal steps to do. First one is to deterimine terrestrial borders of maritime domain and inscribe this borders into land registry. Concessions are only way to economic exploitation of maritime domain. Through this thesis all the types of conccesions and similar legal institutes are elucidated. As a special review in his thesis, concessions of regional (county) relevance is given.