Building on literature in social psychology that discussed betrayal in interpersonal relationships, this article explored betrayal in buyer–seller relationships using data collected from a survey conducted among 109 buyers and 115 sellers in the United States. The results indicated that betrayal was a complex, multifarious, and dynamic phenomenon, consisting of a sequence of phases, namely causes, symptoms, forms, consequences, and therapies, with multiple issues being involved at each phase. Our study also revealed that the views of buyers differed from those of sellers in terms of how various relational characteristics contributed to the emergence of betrayal episodes, what behavior and attitudes helped to diagnose partner betrayal, in which forms the betrayal acts were manifested, how the victims of betrayal felt, and how betrayal problems could be handled in a working relationship. In fact, the various dimensions in each of the betrayal phases examined were consistently more frequently mentioned by buyers than sellers.