The research of Soviet scientists within the field of game theory, starting around 1965 under the supervision of N. N. Vorob`ev, one of the leading experts in the field, has resulted in many high-level publications. The purpose of this book is to report about the highly qualified research by Russian game theorists during the two decades 1968 - 1988 to the international readership. The book contains a collection of contributions in game theory and the related field of equilibrium theory which never had been published in English before. A short historical survey about the development of game theory in the USSR before 1990 is given in the introduction.