In hereditary haemochromatosis, disturbed regulation of iron absorption causes accumulation of iron in the body.Classic haemochromatosis should be suspected particularly in middle-aged men presenting with excessive fatigue, decreased libido, loss of body hair, diabetes, hepatomegaly, joint symptoms, pigmentation of the skin or an unexplained increase of plasma aminotransferase concentrations.Diagnosis is based on determination of iron parameters in serum or plasma and on detection of a gene mutation predisposing to the disease.Liver biopsy is nowadays only rarely needed for confirmation of the diagnosis and for differential diagnostics. Repeated venesections are an effective, cheap and safe form of treatment. By sufficiently early diagnosis and treatment it is possible to prevent the development of late complications of the disease. Secondary haemochromatosis is usually seen in chronic anaemias which are associated with reduced erythropoiesis and the need for repeated red cell transfusions.