This chapter focuses on relevance theory. It first introduces its main tenets, before giving a detailed presentation of the cognitive and the communicative principles of relevance. With this framework in mind, the chapter goes on to illustrate how relevance theory deals with different cases involving pragmatic enrichment. It also introduces the notion of explicature, parallel to that of implicature that was introduced in relevance theory. Finally, the chapter illustrates how some pragmatic phenomena that were previously treated as cases of implicature have been reclassified as explicatures in relevance theory.