The Uricult dip slide was compared to traditional methods of bacterial isolation and quantitation in two different hospital wards. In a chronic care ward for patients with spinal cord injuries, the correlation of the dip slide and pour plate results was 96 per cent; there were very few specimens which had colony counts between 10(4) and 10(5) per ml. In a busy emergency room, the correlation between the dip slide and quantitative loop techniques was 75 per cent. In this population 18 per cent of the dip slide and 2l per cent of the calibrated loop cultures yielded colony counts between 10(4) and 10(5) per ml., and most of these cultures contained a mixture of bacteria. The results show that the Uricult dip slide performs well under ideal conditions. The dip slide can alleviate, but not eliminate, the problem of mixed bacterial growth at 10(4) to 10(5) colones per ml. The usefulness of the slide must be assessed in relation to the patient population and clinical situation in which it is to be employed.