Sleep disordered breathing (SDB), particularly their clinically most serious and at the same time common form-sleep apnoea syndrome-caused by structural or functional abnormalities in the area of upper airways, are frequently linked with other diseases. The accompanying respiratory, cardiovascular, neuropsychic, sympathoadrenal and endocrine-metabolic disorders and their variable intensity determine the character and severity of patients complaints. The coincidence of SDB with alteration in one or another system produces mutual potentiation of their negative effects appearing as serious, not rarely even life threatening acute complications or chronic consequences manifesting exactly in the area of the afflicted system. The paper illustrates on several examples the development of pathological signs of SDB concerning practically all medical branches and at the same time demonstrating the multidisciplinary character of sleep medicine. (Fig. 1, Ref. 27.)