Research extending over twenty years in behavioral decision theory has led to the development of two important research streams--mental accounting and reason-based choice. This paper explores recent research on the role of mental accounting and reason-based choice in the construction of consumer preferences. Evidence suggests that the principles of mental accounting often regulate the purchase and consumption of luxuries and that reasons may play an important part in this process. In particular, buying and consuming luxury goods tends to call for reasons and justification and can evoke intra-personal conflict that might be resolved with the aid of mental accounting. Moreover, reasons can serve as important building blocks in the formation and grouping of mental accounts. The current paper also discusses the construction of preferences as a process where, in certain cases, consumers choose reasons rather than options. Among other things, focusing on reasons can lead to discrepancies between decisions and consumption experiences, preference intransitivity, and unconventional choices. Directions for future research are discussed.