GPCRs are involved in a variety of physiological and pathophysiological processes. So far, much effort has been made on anti-GPCR drug discovery with a focus on the development of small molecules and monoclonal antibodies for the treatment of cancer, infection, metabolic disorders or inflammatory diseases. Recently, functional autoantibodies against GPCRs were identified in various diseases associated with pathogenesis, uncovering a potential new field of therapeutic intervention. Thus, the aim of this journal is to combine the current knowledge about the role of GPCRs in different pathologies, their mode of action and state-of-the-art research techniques to identify common fundamental pathways that can be transferred to other disease entities with similar manifestations.