Behavioral economics is a research field that studies decision-making behavior in real decision-making situations. Our decisions are not always as rational as we believe; very often they are irrational, i.e., they contradict the predictions of the standard model of homo economicus. However, there are also generally valid patterns behind irrational behavior, meaning that irrational decision-making behavior can also be predicted. This chapter provides a brief overview of behavioral economics and links its approaches with predictive modeling methods. This enables the modeling and forecasting of customer behavior in new decision-making situations, such as the acceptance of new products or services, and thus helps to derive optimal courses of action.