Skinner proposed that self-knowledge is a consequence of social contingencies which place the individuals' reports under the control of their own behavior. The above has been corroborated by several investigations on human and nonhuman subjects. Investigations have shown that different aspects of the relationships between the organisms behavior and its consequences may have a discriminative control on the organism's descriptions (self reports). A review of the literature on contingency discrimination is given, highlighting the controlling functions of certain characteristics of contingencies that maintain the behavior to be described and those that maintain the self-report behavior. Several implications of these studies on day-to-day life are also discussed.