The psychometric properties of behaviors in economic games as indicators of stable latent dispositions of altruism and fairness were tested in two studies. Using latent state-trait analyses, we explored the factor structure of offers in the dictator game, rejection decisions in the ultimatum game, and altruistic punishment and altruistic compensation in a three-person game. Results showed that four distinct but intercorrelated latent dispositions best described the interindividual differences in these behaviors. The reliabilities and stabilities of these behaviors across 6 weeks were generally moderate to high. Correlations with self-report measures of personality suggested that offers in the dictator game and altruistic compensation reflect a concern for fairness coupled with a reluctance to harm others. Rejection decisions in the ultimatum game were correlated with competitiveness and the need for power. In sum, our results suggest that economic games have good psychometric qualities as instruments that can be used to assess stable latent dispositions and can be employed as objective personality tests sensu Cattell to gain a more complete picture of personality beyond self-reports. © 2013 Hogrefe Publishing.