Research on relational exchange has focused primarily on long-term, or "enduring," relational exchange. The evolutionary model of relationship development that is the foundation for much of the research on enduring relational exchange lacks applicability for short-term, or "interimistic," relational exchange. Interimistic relational exchange is defined as a close, collaborative, fast-developing, short-lived exchange relationship in which companies pool their skills and/or resources to address a transient, albeit important, business opportunity and/or threat. Because interimistic exchange relationships must quickly become functional and have a short life, these relationships have less time to fully develop the relational governance mechanisms assumed in the evolutionary model. Therefore, interimistic relational exchange appears to rely more on nonrelational mechanisms than does enduring relational exchange. This article (1) examines how interimistic relational exchange governance differs from that of enduring relational exchange and (2) develops propositions for further research on interimistic relational exchange.