Competition refers to the economic structure among entrepreneurs and involves the allocation of supply and demand resources in the market. It is a continuous battle between larger and smaller competitors offering products or services to a larger number of customers in order to achieve certain business goals in order to achieve as much profit as possible as well as higher market share. The protection of competition has the purpose of creating benefits for consumers as well as a level playing field for entrepreneurs in the market. In order to achieve this, numerous legal regulations are used both in the Republic of Croatia and in the European Union. In the Republic of Croatia, the protection of competition is regulated by the Competition Act, which regulates the rules and the system of measures for the protection of competition. The Agency for the Protection of Market Competition is a legal entity that has public powers and can independently and independently perform tasks within the scope and competence of the aforementioned laws. Competition in the European Union aims to ensure that the internal market functions effectively. The accession of the Republic of Croatia to the European Union directly applies the provisions of the acquis governing the field of competition in the EU, Articles 101 and 102 of the Treaty on the Functioning of the EU (TFEU), which state prohibited agreements and abuse of on trade between the Republic of Croatia and EU member states. Within this paper, the case was analyzed where the managers of residential buildings from Split and Pula violated the right to compete by agreeing on the prices of their services.