Chronic immunological processes that underlie persistent viral infections and autoimmune disorders such as multiple sclerosis can be relapsing–remitting in nature. The progressive loss of β-cell mass during the development of autoimmune type 1 diabetes (T1D) can also be non-linear, but the exact nature and kinetics of the immunological processes that govern T1D are not known. Here, we propose that the immunological process that is at the root of T1D is relapsing–remitting in nature and discuss the unresolved controversies and therapeutic implications of this hypothesis.