A psychosomatic study was made of eight children with Sydenham's chorea. The children ranged in age from 7 to 16 years. Three patients had a history of rheumatic fever and three had no evidence of rheumatic disease; in two patients the evidence for rheumatic fever was equivocal, one probably having had it and the other probably not. The eight children were found to be emotionally quite disturbed. Their personality structure was characterized by a triad of (a) marked passivity, (b) schizoid withdrawal from people, with two of the children being frankly schizophrenic, and (c) much underlying anxiety. Obsessive, phobic and depressive features were separately present in some of the children. In five cases the onset of Sydenham's chorea closely followed an episode of marked emotional stress, and in two others the correlation of chorea with emotional stress was equivocal. The literature was reviewed, and it was pointed out that in over half of all reported cases of Sydenham's chorea evidence of rheumatic fever could not be found. It is felt that Sydenham's chorea can be understood only as a psychosomatic illness potentially caused by a number of agents acting individually or jointly, and varying in their respective importance from case to case. Severe personality disorder and rheumatic fever are two such etiologic agents which may be operative in Sydenham's chorea. The importance of further psychosomatic study and experimental psychotherapy in the comprehensive medical study and management of children with this disorder is emphasized.