The article is devoted to the analysis of the civil law concept of private international law, which comes down to the fact that private international law regulates private law relations: civil, family and labour, if they comprise a foreign element (foreign citizenship, foreign affiliation of a subject of law, etc). The authors provide arguments that private international law is an independent branch of law and legal studies; civil law concept of private international law is based on two methods of regulation of private law relations with a foreign element: conflict of laws (national and standardized through uniform rules contained in international conventions) and a substantive (standardized) element. The authors reveal the role in the development of the science of private international law played by professor L. A. Luntz, Laureate of the USSR State prize, who worked in the Institute of Legislation and Comparative Law (ILCL) in 1939—1979. Special attention is paid to the contribution of L. A. Luntz and his successors — the ILCL researchers V. P. Zvekov, A. L. Makovskiy, N. I. Marysheva, O. N. Sadikov — to the formation and development of the Soviet and Russian legislation in the field of private international law, including drafting of the Bill on Private International Law and International Civil Procedure (1990), drafting and adoption of the respective sections within the Fundamental Principles of Civil Legislation of the USSR (1961, 1991), the Fundamental Principles of Marriage and Family Legislation of the USSR (1968), the RSFSR Civil Code (1964), the Marriage and Family Code of the RSFSR (1969), the present Civil Code of the Russian Federation (Part III, 2001), the Family Code of the Russian Federation (1995), the Maritime Code of the Russian Federation (1999), the Civil Procedure Code of the Russian Federation (2002).