This chapter surveys the contributions of the WOA workshop series to the area of interaction protocols for communicating agents. Interaction protocols are among the main means for agent coordination, and have drawn the attention of many researchers within the WOA community, and internationally, since the effectiveness and scalability of a distributed systems may strongly depend on how interacting protocols are specified and implemented. The chapter reviews the diverse approaches in literature starting from message passing, with protocol specifications in FIPA ACL, KQML, and AUML, and implementations in well-known platforms and systems like Jason, JADE and SARL. Then, the chapter explores the alternative approaches relying on the environment as a means of coordination, and briefly introduces proposals such as CArtAgO and JaCaMo. Environments allow the realization of agent organizations, where MOISE is particularly important since it is also representative of normative multi-agent organizations. Specifically, in organizations, agents are expected to abide by the rules encoded by the interaction protocols. Consequently, great attention was posed to a priori conformance verification and to monitoring the run-time behavior of the agents. Social approaches have then emerged as an alternative solution to the specification of an organization. We briefly survey social commitments and their use for defining interaction protocols, and some proposal for introducing them in agent platforms. More recently, the focus has shifted to the information that is exchanged, leading to the proposal of information-based interaction protocols.