The subject of this paper is tourism in the Republic of Croatia. According to the World tourism organization (UNWTO), tourism comprises the activities of persons travelling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes. Tourist is a person who travels out of his usual environment for not more than 12 months and whose main purpose of trip is not tied to the performance of some lucrative activities in the place he visits. Special attention is paid to tourism activities in the country, respectively to arrivals and overnight stays of domestic and foreign tourists in commercial buildings in the Republic of Croatia. The first part of the paper deals with the very history of tourism and tourism resources and regions of the country. The second part of the paper refers to theoretically defined relative numbers of structure, dynamics and coordination and ways of calculating and explaining of results. In the final part of the paper, relative numbers are applied to a concrete example, arrivals and overnight stays of tourists in the Republic of Croatia.