Tourism is a complex socio-economic phenomenon that integrates a whole numerous sciences and requires an interdisciplinary researching approach. In the context of the tourism complexity, marketing in tourism and the concept of sustainability have a range meaning. In the contemporary, time that is marked by a numerous changes, sustainable tourism development becomes an imperative and the only appropriate, long-term, profitable and justified approach of business and development. Numerous scientists in the present day deal with this issue and try to point to the key segments that determine the performance of sustainable development. Within that, special importance is the quality of the implementation of the marketing process in tourism. Marketing in tourism has many functions as well as positive impact on the implementation of sustainable tourism. In that sense, it is possible to discuss about the socially responsible marketing that promotes the fundamental values and principles of sustainable development. In addition, marketing in tourism has a positive impact on informing the general public, implementing education, enhancing cooperation and bringing stakeholders closer together and in a row.