The emergence of Behavioral Economics profoundly transformed the traditional understanding of decision-making processes. Since the pioneering work of Daniel Kahneman and Amos Tversky, and later Richard Thaler, it has been established that decisions made under uncertainty do not conform to expected rationality but are instead shaped by heuristics and cognitive biases. This approach has redefined multiple disciplines, such as finance, marketing, and public policy, by demonstrating that human behavior is predictably irrational and that this irrationality can be influenced through decision architecture strategies. However, in the field of medicine, and particularly in surgical practice, the literature remains limited despite the significant impact that biases can have on clinical decision-making. This chapter introduces the psychological and economic foundations of decision-making and highlights the importance of understanding cognitive biases in surgical practice.