Although the chronic destructive joint processes dominate the clinical picture of chronic rheumatoid arthritis, it must not been forgotten that the disease is a systemic one, whereby certain organs or organ systems are affected either clinically or subclinically. The various possible pathogenetic mechanisms are discussed and the particular type of patient with rheumatoid arthritis who appears to be prone to extra-articular manifestations is described. Subsequently, the individual organic manifestations and the clinical picture are discussed, as well as the incidence and significance of these features.