The article examines the prevailing approaches to the definition of public-private partnership (PPP) in foreign countries and the Russian Federation, the main essence of this institution in various legal systems. The purpose of this article is a comparative legal analysis of the key features, trends and opportunities for improving this form of interaction between government and business, based on the research conducted by the author. The subject of the article includes legal, economic and organizational models of PPPs, their implementation in various sectors of the economy, as well as a comparative assessment of effectiveness in the Russian and international context. The research methods used are comparative legal analysis of the legislation of Russia, Europe, Asia and North America, as well as a review of the reports of some international intergovernmental organizations. Special attention is paid to expert assessment and review of scientific publications, which allowed us to identify common and specific features of PPP models. Having studied the doctrinal approaches to defining the essence of PPP, the features and specific features of this modern legal institution and instrument, the author proposed his definition of public-private partnership, which focuses more on the use and implementation of modern technologies, which is designed to improve the quality of life of society.