The article considers competition in taxation as the condition for territories’ development and the forms of its implementation among regions. Studies of the theoretical aspects of competition in taxation emergence allowed concluding that primarily social relations are its basis. The author defines the concept of competition in taxation as the process of competitive privileges regulation while dealing with public law establishments to share the tax base by attracting mobile production factors and other advantages to achieve sustainable competitiveness. The author also adds her own features to the classification of competition in taxation. The application of this classification helps deeper understanding of this phenomenon in its versatility. Considering tax competition among the Russian Federation subjects in finance-budget sphere allowed seeing several stages in the development of competence in taxation among regions from its implementation through violence to the correct application of fiscal policy tools. The research revealed the main prerequisites of the development of regional competition in taxation in Russia, and provided the ways and measures of its regulation among the RF regions by the state. The duality of the implementation of regional taxation competition’s inner potential is demonstrated through the main directions of its ultimate impact via the fiscal and regulation functions. Considering the forms of the implementation of tax competition among the RF regions provided the opportunity to prioritize among the regional taxes, which allow influencing the competitive advantages of the territories in order to attract investors in their regions. The review of the regulations of all regional authorities allowed making a conclusion about the existence of different positions on participation in competition in taxation. The research demonstrated that most efficient and available forms of taxpayer involvement are establishing additional benefits on regional taxes, differentiation of the income tax rate (its regional part), and that most regions using the tools of competition in taxation bet on the increase of investment attractiveness of their territory Highlights 1. Competition in taxation is the process of regulation of competitive privileges in the process of social establishments interaction aimed at the sharing of tax bases at the expense of involving mobile production factors and other advantages in order to achieve and keep sustainable competitiveness 2. It is expedient to add two more characteristics — the parameters’ size and the vector of the impact — to the tax competition classification 3. The vertical tax competition by offering tax benefits has objective limitations at the present stage in the Russian Federation 4. There are various positions among the subjects of the Russian Federation on participating in tax competition, most regions rely horizontal competition in taxation through the means that support investment activity at their territory For citation Troyanskaya M. A. Competition in Taxation and the Forms of its Implementation among the Subjects of the Russian Federation. Journal of Tax Reform , 2017, vol. 3, no. 3, pp. 182–198. DOI: http://dx.doi.org/10.15826/jtr.2017.3.3.039 Article info Received October 1, 2017 ; accepted November 13, 2017