Expectations provide organizations with information and cues about their stakeholders’ and publics’ values, interests, experiences, and knowledge. This chapter argues for a move that takes expectations beyond the current cursory level for different areas of public relations - reputation management, corporate responsibility, issues management, and legitimacy - toward explicit theoretical understanding and models for addressing expectations. The chapter introduces expectations as an intersecting phenomenon in public relations research and builds postulations for theorizing expectations in public relations by reviewing theories that address expectations in relationships, and by exploring different conceptual meanings of expectations. As a result, the chapter introduces Relationship Expectation Theory (RET), which places expectations in the domain of public relations. RET acknowledges different expectation types, the context of organizational relations, and organizations’ limited ability to influence expectations.