The chapter analyzes relationship marketing as a paradigm shift in marketing by considering the emergence of the concept in close connection with previous marketing management orientations. It explains why a relationship marketing approach is needed and presents the main perspectives and principles of relationship marketing, by emphasizing customer loyalty effects on business profitability, the importance of increasing customer interactions and customer value for long-term effectiveness, the role of internal marketing for employee performance and customer satisfaction, and the mutual dependence that is created between stakeholders as a result of cooperative relationships. Then, the leading research groups and areas for relationship marketing implementation are highlighted, focusing on industrial and services industries and considering mass consumer markets and nonprofit sectors. In the end, evidence of relationship marketing practices on the Romanian market is described, followed by concluding remarks about the role of technology in the concept evolvement.