International Tourism Development Determinants After the World War II international tourism became a mass phenomenon. Actually more and more people travel, more countries become tourist destination, and travelling became very important in man's life. The paper describes the most important determinants of tourist market development. It is difficult to classify these determinants, so the author aims to try to classify the determinants as the direct and indirect ones. The indirect determinants of tourist market development are: amount of spare time, means (transport development, industrialisation, urbanisation and other. The most important direct determinants are: tourist promotion and advertisement, information development, tourist policy of the country and activity of the international tourist organisations. All the mentioned above are described in the paper.