Using clinico-epidemiological research methods, the authors have studied 260 schizophrenic patients in whom the disease was first manifested in the period when wide-scale combined rehabilitation programmes were under way. It has been demonstrated that the incidence of chronic schizophrenia shows no tendency to decrease despite the use of modern rehabilitation methods. Chronicity itself has become more variable in its manifestations; thus the population of "chronics" is mostly made up of young people. An analysis of the time-course of invalidization of schizophrenic patients in the first four years of the disease has indicated a clear-cut peak at the second year after the manifestation of the process. The findings obtained made it possible to describe a number of parameters of functioning of "chronic patients of a new type". It has been shown that these patients are young and characterized by a comparatively short duration of the disease, frequent rehospitalization, marked manifestations of social disadaptation in the presence of externally normal behaviour due to rapid incapsulation of the current symptomatology, formally intact familial ties and a high frequency of abnormal behavioural manifestations.