Rusia
This article represents and defines the concept and criteria for filling the category of "reasonableness" as a special valuation concept, widely used in the legislation on contract system in the Russian Federation and other countries, in particular the USA. Clarification of its essence is of great importance for the purpose of applying this legal category in lawmaking and law enforcement activities, first of all, to achieve maximum effectiveness of the operation of legal norms and observance of the principle of fair competition in concluding and executing contracts aimed at satisfying the public needs.The general methodological basis was formed by the general scientific (dialectical) method of cognition, comparative, logical methods that allowed considering the problems of the development of civil legislation in the sphere of satisfying the state and municipal needs.We presented and analyzed the theoretical studies of scientists in this field, as well as the latest judicial practice of Russia. We proposed to reform the current federal law of the Russian Federation on the contract system.