This paper outlines the theoretical foundations of Soviet psychology, analyzes major themes based on these foundations, and identifies relevance of Soviet psychological research for American investigators. Basic social and political factors that influence Soviet research include centralization of all scientific and academic endeavors and orientation of all psychology research toward the ideals of Marx and Engels. Major themes which govern psychological research are: 1) a genetic (developmental) theory which maintains that behavior can only be understood as the history of behavior; 2) a social interaction theory (human nature can be understood by examining human productive activity such as labor); 3) mediation (human psychological systems are mediated by sign systems such as speech and behavior patterns); 4) internalization (transfer of external actions to the plane of reflection); 5) motivation and intent (understood as a link between psychological processing and social action); and 6) goal setting (objectives of various activities at various levels of consciousness). For each of these themes, excerpts from major Soviet research works are presented and analyzed. Implications for western psychology research are related including that western researchers have largely ignored the importance of the regulative functions of speech, historical processes, the relationship of thought to language, and the relationship of cognitive processes to the overall nature of activity. (DB)