Introduction. Fiscal policy instruments and their effective management process are the keys to overcoming economic fluctuations and achieving economic development. Only qualitative and effective tax, expenditure and debt public policies can provide fiscal sustainability in the country and competitiveness in the global economic environment. At the same time, the desired result in the social and economic area can be achieved only in a complex, ensuring an equilibrium state in the implementation of measures in each of these areas. Therefore, the study of the problem of forming a fiscal and sustainable environment, the development of a clear strategy for social and economic development, based on the use of an effective model of fiscal policy, and the achievement of a qualitative combination of the main parameters of tax, expenditure and debt systems in the process of forming an effective economic doctrine of the country as a whole, is of paramount importance to the present day. Such analysis will allow obtaining qualitative scientific results and making the necessary conclusions. In particular, the analysis of the essence and main features of fiscal sustainability, the development of different approaches and methods for its determination, the place of such an indicator in shaping the parameters of fiscal policy in particular and the strategy of economic development in general, will allow to highlight the strengths and weaknesses of domestic fiscal policy, as well as to distinguish the main challenges, which Ukraine faces on the way to achieve a stable social and economic environment.

Methods. In the course of the research, general scientific and empirical methods of economic science based on a systematic approach have been used. They are the dialectical and logical method, method of analysis and synthesis, method of generalization, graphical method, and method of scientific abstraction. These methods have been applied in order to study the essence of fiscal sustainability, the impact of such an indicator on the economic conjuncture in the country.

Results. The article deals with the essence of fiscal sustainability, on the basis of which the actual interpretation of this concept has been developed. According to this concept the indicator of fiscal sustainability is an indicator, which indicates the government's ability to pursue an effective fiscal policy in order to ensure the development of the economy, overcome economic imbalances and identify threats to economic crises, and prospects for economic growth.

The paper considers different methods for fiscal sustainability determination. It has been established that each method involves different parameters and cannot be effective for all countries. In particular, some of them can be used in countries with developed economies, high fiscal space, but they will not be suitable for countries whose economic and social development is worse or whose social and economic status is rather low. Therefore, in order to calculate fiscal sustainability, it is important to undertake a thorough analysis of fiscal and social and macroeconomic indicators.

Perspectives. The results of scientific research can be useful for scientists and practitioners who deal with fiscal policy issues in the area of anti-cyclical and anti-crisis economic regulation.

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