In their review the authors discuss the history of Alport's syndrome, its nomenclature, incidence, genetics, clinical diagnosis. The authors emphasize electron microscopic findings and criteria of the diagnosis (haematuria or renal failure in the family, progressive nervous deafness, typical changes of the basal glomerular membrane (GBM) and ophtalmological findings of lenticonus or perimacular spots. Familial haematuria (FH) is according to the authors defined as haematuria in several members of the family. Based on data in the literature and the authors' experience, the authors discuss the differential diagnosis of FH where Alport's syndrome is relatively rare. A far more frequent unit is benign familial haematuria characterized morphologically as isolated thinning of the GBM. In some cases these patients are threatened by iatrogenic damage from unnecessary and invasive diagnostic method. The finding of thinned GBM and normal renal function in the parents and grandparents suggest a favourable prognosis also in child patients. Cases of familial glomerulonephritis or idiopathic syndrome with glomerulosclerosis or familial IgA nephropathies are relatively rare. Familial haematuria is are relatively rare. Familial haematuria is relatively frequent (according to the authors 20% of all obscure haematurias) and their diagnosis is based on systematic examination of the urine in other members of the patient's family who also suffer from haematuria.