Purpose – The purpose of this paper is to provide alternatives to the economic man image of human behavior and incorporate these alternative images which are based on motivational needs into utility analysis. Design/methodology/approach – Empirically derived psychological variables define the individual’s personality type in terms of an altruistic or non-altruistic orientation. These variables are incorporated into the individual’s utility function, and an analysis is made of utility maximization based on human needs. Findings – Behavioral and motivational characteristics of individuals are relatively constant and are a function of the underlying personality traits of the individuals. Empirical support is offered for these characteristics, they are incorporated into the individual’s utility function, and an analysis if performed on the interactions between individuals. Originality/value – This paper not only goes beyond the economic man image of human behavior to analyze altruistic and selfish behavior but also analyzes the utility functions of both potential donors and recipients