The article presents an analysis of approaches to the content of the concept of «sustainable development» and an analysis of methods for its assessment. The relevance of the research topic is substantiated by trends in the greening of the economy and the spread of the «green economy». These trends have formed, including taking into account the Sustainable Development Goals adopted by the UN. Achieving these goals has been identified as the key idea of public administration in many countries. However, in practice, the reorientation towards a «green economy» triggered the emergence of an energy crisis. Under these conditions, it seems important to understand the concept of sustainable development and the formation of an adequate methodology for its assessment. The purpose of the presented study is to study approaches to assessing sustainable development and approbation of the proposed methodology for assessing it using the example of the regions of the Volga Federal District for 10 years. The work substantiates the identification of such elements of sustainable development as economic, social and environmental sustainability. The factors and indicators that determine them are analyzed. A brief description of the existing methods for its assessment is presented. The necessity of forming an appropriate methodology for assessing sustainable development, which is not overloaded with indicators, has been proved. Indicators for the assessment of seventeen basic blocks in the context of the UN Sustainable Development Goals were formed and substantiated. As a methodology, the application of the standardized deviation value method is proposed. The results obtained made it possible to identify problem areas in its sustainable development, visualize and characterize the direction of its development. The findings of the study can be used as an information base in the development of programs for the socio-economic development of the territory.