Red cell urinalysis is a very common laboratory procedure in health care, and microscopic haematuria a common finding in apparently healthy people. Response to a questionnaire sent to all departments of urology in Sweden and to general practitioners in the province of Ostergötland showed both groups to vary considerably in their approach to its management. Accordingly, to determine whether a reliable scientific basis exists for its management, a literature search for the period, 1975-97, was made in MEDLINE, under the headings haematuria, microscopic haematuria and microhaematuria, which yielded a total of 845 items. After scrutiny of the abstracts, 203 reports were selected for closer study in the following respects: study design, series studied, selection criteria, age and gender distribution, test methods used, cut-off values for further investigation, and study results. In 17 series comprising a total of 5,000 patients, urological cancer was diagnosed in less than three per cent of cases. Of almost 200,000 males and females patients tested for haematuria, less than one per cent were found to have disease requiring treatment. In general, the studies were characterised by an absence of control groups, and by differences in study design, selection criteria, test methods, definitions of microscopic haematuria, and investigatory procedures. There were no randomised prospective studies where patients undergoing investigation were compared with those undergoing follow-up only. Thus, as available documentation in professional journals and textbooks shows no consensus to exist as to management in cases of microscopic haematuria, further research is required in this field before scientifically sound guidelines can be issued.