The authors present their own observation of five child patients with Münchhausen's syndrome and Münchausen's syndrome by proxy resp. Both these units are included in the wider framework of the syndrome of the battered child. Four boys and one girl are involved, aged 12-16 years. In all instances the reason for admission to hospital was macroscopic haematuria. The children were prior to hospitalization subjected to a series of various invasive examinations, incl. repeated examinations under anaesthesia to elucodate the cause of macroscopic haematuria. The uncommon course of the "disease" and results of the examinations led in four of the five children to suspicion of Münchhausen's syndrome. Based on this suspicion after immobilization of the patients associated with prevention of manipulation with the hands, macroscopic haematuria disappeared as well as haematuria in general. In the fifth patient Münchhausen's syndrome by proxy was involved. The patient was referred because of repeated attacks of macroscopic haematuria a renal biopsy. The authors analyze in more details the individual case-histories and in the conclusion to they raise their objections to the opinion that these two syndromes are extremely rare.