Because they mainly address different questions, functionalist and Marxist theories are often assumed to be incommensurable explanations of the distribution of rewards in society and, therefore, the theories cannot be competitively tested. But close examination of the two viewpoints suggests that despite many differences, the theories share two analytical elements in common. These aresocial powerandevaluation of contributionas determinants of the concrete distribution of rewards. While the theories diverge widely in the emphasis they give these two elements in their explanations, the presence of common analytical elements makes possible a competitive test of the ability of each theory to explain variance in concrete systems of differentiated reward. Four questions encompassing such a test are posed.