Abstract <p>Professor Boris Yakovlevich Spivakov (May 19, 1941—April 08, 2022), Doctor of Chemical Sciences and Corresponding Member of the Russian Academy of Sciences, was a prominent scientist in analytical chemistry who made a substantial contribution to the development of liquid extraction theory and to the expansion of its applications. He led a series of studies on the extraction of water-soluble metal complexes in aqueous two-phase systems based on water-soluble polymers. At the Laboratory of Preconcentration Methods at the Vernadsky Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences, which he directed from 1990 to 2016, researchers actively advanced both the theory and practical applications of membrane filtration, solid-phase extraction, and liquid chromatography with a free stationary phase. Spivakov also proposed a comprehensive set of methods for the fractionation, investigation, and analysis of nano- and microparticles of natural and anthropogenic origin. He authored more than 300 scientific papers, inventions, and monographs. In 1986, he received the L.A. Chugaev Prize of the USSR Academy of Sciences for a series of works on complex formation in extraction, and in 2004, he received the V.G. Khlopin Prize of the Russian Academy of Sciences for developing new methods for the separation and concentration of substances to address analytical, preparative, and technological problems in radiochemistry. This article presents bibliographic information and an overview of the diverse scientific contributions of B.Ya. Spivakov.</p>