journal of consumer
. The nature of sales management also changes in response to the changing nature of personal selling . While each of these selling roles may have dominated buyer-seller exchanges in these eras, all of the roles were represented in each era . Thus, in the 1990s, selling and sales management in some situations is more consistent with the nature of selling in the production, sales, or marketing era than in the partnering era . In fact, these other prototypical selling roles may dominate buyer-seller relationships in the 1990s even though the 1990s are identified with the emergence and growing importance of the partnering role . In our discussion of the evolution of personal selling, we will emphasize the different roles that have emerged rather than the nature of personal selling in different eras . We also recognize that sellers have a portfolio of relationships with their customers (Lambe and Spekman 1997) . Some of these relationships are based on transactional exchanges associated with the production and sales roles, and others are based on relational exchanges associated with the partnering role for salespeople . This article centers on the partnering role for salespeople due to the growing importance of relational exchanges and limited research examining the partnering role of salespeople . While transactional exchanges may dominate the portfolio of most sellers, the relational exchanges provide the greatest opportunity for developing strategic advantage and realizing extranormal profits from exchange relationships .