In this paper the authors consider tourism as a geographical phenomenon, which can be evaluated and used in geographical perspective to understand the forms and functions of tourism resources along with the specifics of its demand. Tourism is one of the tools to achieve sustainable and balanced development of the region. The authors analyze the concept of "tourist space"" and "tourism industry", which resulted in the conclusion that, in essence, they have a very long and close connection with the local and spatial aspects and elements. The article discusses various approaches to the study of tourism sustainability, their relationship with spatial concepts. In order to introduce into use and to assess such complex concepts as sustainability or sustainable development, the article uses well-known structures, such as prism of sustainability. In particular, the indicators proposed by the United Nations (UN CSD), the World Tourism Organization were considered. The analysis allowed to define "stability of the system" as its ability to remain relatively unchanged (to keep its structure and functional features) within certain time frame despite external and internal disturbances. At the same time, one can distinguish three types of sustainability, related to spatial factors: 1) positional stability - relatively static notion and it reflects fixity of the elements of the system in a given area, it is connected with the existence of systems and their components; 2) structural stability - a concept that reflects the links (real and potential) between the elements of the system or different systems and has a static-dynamic nature; 3) functional stability defines the dynamics of systems, the actual existence of spatial interactions between elements of the system and other systems.