he latest global and domestic trends of changes, transformations and transformations in various spheres of social life, spheres of human activity and aggregates of social relations determine the necessity of adopting, changing and supplementing individual acts of legislation in general. This happens not only to achieve the need for regulation in new conditions and circumstances, but also to increase the effectiveness of this regulation. That is, the transformation of legislation to meet today’s needs is one of the components of its effectiveness. The purpose of the article is to provide a definition of the concept of transformation of legislation and an exposition of its main components, it is also planned, based on the scientific works of scientists, to highlight examples of branches of law in which this phenomenon occurs, to consider the relationship between the transformation of legislation and its effectiveness. The specified problems are considered in the article and it is established that the transformation of legislation (as a certain process which includes mandatory and specific components and successive stages) takes place at different levels and spheres of regulation of social relations, but primarily the transformation of legislation takes place in those sectors of society and states, directions of human activity, challenges and requests in which, by the fact of their occurrence, precede the existing legislation and require regulation and regulation. Digital and IT technologies, European integration processes, the latest interpretation and understanding of the Basic Law in the spirit of the priority of human and citizen rights, the defense of the country in the conditions of a large-scale military invasion of the Russian Federation and the repulsion of armed aggression (with the subsequent de-occupation of territories), processes of globalization and deep integration of Ukraine into them - these are the driving forces, factors and specific reasons that force the legislation to transform and to which its transformation is directed at the same time. The transformation of legislation can contribute to the achievement of social effectiveness of legislation, and the effectiveness of legislation in turn depends on the degree of compliance of legislation with the basic principles of the rule of law, such as the principle of legality, guarantees of human rights and legal certainty of citizens. As for the relationship between the social effectiveness of legislation and its transformation, it should be noted that the improvement of the quality of legislation as a result of its transformation and its effective coverage of the priority areas of international relations, the state, society and a specific person are clear markers and indicators of its effectiveness. Key words: legislation, law, law, effectiveness, transformation, transformation of legislation, modernization of law, specification of tasks and prescriptions of laws, implementation of laws, effectiveness of legislation, social effectiveness of legislation, concept, definition, components, process.