The primary goal of this paper is to theoretically explain the concept of sustainable tourism development, and to point out the importance of its implementation. In addition, the aim of the research conducted among the stakeholders of the tourist offer of the City of Kaštela, was to determine attitudes about the effects of tourism development, and the application of sustainability measures. Sustainable development is an ongoing global process that is of great importance for tourism, but also for the community. It was created in response to the growing awareness and concern of countries about the negative consequences that mass tourism has on the environment. The solution to the effects that tourism generates lies in the sustainable development of tourism, which takes into account the needs of primarily the local population, but also tourists and tourist destinations, while protecting and improving the destination's porential for the future. The research found that half of the respondents implement only small amount of measures in their business, and that the respondents from the private sector apply less sustainable measures than the respondents from the public sector and civil society organizations. Also, there is a statistically significant difference in the assessment of the negative effects of tourism by type of key stakeholder. Furthermore, there is a statistically significant negative correlation between the negative effects of tourism and the application of sustainability measures, which means that those respondents who apply sustainability measures in their business agree more with the positive, than with the negative effects of tourism. By applying sustainability measures, the positive effects of tourism are achieved to a greater extent, so it is important to apply sustainability measures in the business of each stakeholder in the tourist offer. They are the ones who have an imporant role in shaping and creating a quality and competitive tourist destination that operates in a sustainable way. In order for the destination to be successful and recognizable on the market, mutual cooperation of all stakeholders is crucial.