We report a case of malignant hyperthermia in a man of 41 years during his 13th general anaesthesia. All previous anaesthetics were quite normal. Musculoskeletal abnormalities and increased CPK-levels are to be found in some members of the patient's family. The combined use of suxamethonium and halothane might have caused the development of malignant hyperthermia. As a concept of the aetiology of the syndrome the case history indicates that it may be stress-related.