A completely new situation has been created on the international tourist market over the last ten years. The development of technology brings changes in the market structure while the application of marketing which allows the action of the concentration of tourism entities. Under the pressure of increasing competition, tourism entities are integrated with each other, which allows them to compete in price and quality. New technologies, new consumer profiles and changed economic conditions are the cause for the development of new markets. Quality positioning in a competitive and dynamic tourism market is caused by monitoring modern trends through which demand trends, market opportunities, areas for profitable investments and infrastructure support are monitored. The thesis explores international organizations operating in the field of tourism. In addition to recording international tourist traffic, international organizations recognize the threats of tourism and try to point out potential threats with their guidelines and actions. International organizations provide guidance on how the function of national organizations can be regulated. International organizations play a key role through their actions that are in the interest of the tourism sector. In the beginnings of their activities, they passed regulations related to the provision of facilities during travel, such as passports, visas, border crossing formalities and the like. They also took care of the tourist’s luggage and his personal belongings. Today, by applying the new strategy and guidelines, they focus on the protection of the rights of tourists as consumers, and the protection of historical and cultural heritage and the preservation of ecology. The Croatian National Tourist Board is a particularly important national organization in tourism. In addition to this role, the national organization has an important role in planning and implementing joint strategies, and is in charge of promotional activities with the sole aim of raising the quality level of the overall tourist offer of the Republic of Croatia. The contribution of the thesis is evident through the research. Research has multiple goals. The first goal is to determine the extent to which respondents recognize international and domestic tourism organizations and institutions. The second goal of the research is to determine the extent to which respondents understand and know the role and importance of organizations / institutions. The third goal of the research is to determine the opinion of the respondents to what extent they recognize the interconnectedness and influence of international tourism organizations and Croatian organizations and institutions in tourism.