This dissertation investigates how customer service providers identify psychologically with their customers, as well as how this identification is influenced by an organization's treatment of customers, and how customer identification ultimately affects service performance. Based on predictions made from relational models of fairness and social identity theory, I hypothesize that an employee's perceptions of organizational fairness antecede identity cognitions related to the organization and its customers, and that these identity variables then influence service behaviors. These predictions are tested in two lab studies utilizing a simulated electronic help desk experiment. Results show that an organization's customer-directed fairness affects an employee's customer identification, while employee-directed fairness affects organizational identification. Results also show that customer identification and organizational identification interact to affect the level of politeness demonstrated by service providers, and that customer-directed fairness influences pro-customer rule breaking independently of identity variables. Theoretical and practical implications are discussed.