There is a preponderance of research documenting the benefits associated with adopting a relationship marketing (RM) strategy. However, there is a nascent stream of literature which suggests the adoption of an RM strategy may actually diminish organizational performance. In this chapter, the authors introduce and operationalize a set of dark side constructs. The goal is to examine the influence that relational constructs such as trust, commitment, and satisfaction have on the emergence of this dark side. The influence the dark side has on performance is also tested. The results of the study (N = 309) support the premise of positive relationships between relational constructs and the dark side. Although time was thought to moderate these relationships only the main effects between the relational constructs and the dark side were significant. Performance is found to be negatively influenced by the dark side. The authors discuss the theoretical and managerial implications of these findings.