Using a clinical case which was brought to their attention as a starting point, the authors reexamine the problems relating to the nosographic, etiological, pathogenetic, pathoanatomical and clinical aspects of relapsing polychondritis, as well as those concerning its differential diagnosis and therapy. In particular, they review the various theories of immunological pathogenesis related to the alterations in collagen observed in relapsing polychondritis and in other correlated diseases.