The high-affinity Fc receptor for IgE (FcεRI), a multimeric immune receptor, is a crucial structure for IgE-mediated allergic reactions. In recent years, advances have been made in several important areas of the study of FcεRI. The first area relates to FcεRI-mediated biological responses that are antigen independent. The second area encompasses the biological relevance of the distinct signalling pathways that are activated by FcεRI; and the third area relates to the accumulated evidence for the tight control of FcεRI signalling through a broad array of inhibitory mechanisms, which are being developed into promising therapeutic approaches.