||This thesis focus on two fundamental questions: motivation of altruistic behavior and mutual relation between altruism and egoism within microeconomic theory. Interpretation of altruistic motivation considers latest sociological, psychological and biological theories. In conformity with motivation theory, second part grapple with relationship between altruism itself and standard microeconomic hypotheses. Thanks to revolutionary model of G.Becker that kind of behavior is consequently interpreted by standard economic tools not only in case of individual consumer, but also concerning company surviving in the open market economy. Last chapter pays attention to the altruism in the society with respect to the “other side of paradise” claiming altruism is not always sweet.