Assessment of the value of test strips for demonstration of white cells in urine (Cytur-test) in 161 out-patient urine samples showed that a quick method such as the Cytur-test is no substitute for conventional methods. In hospital nephrology out-patients methods such as the Addis count or the investigation of urine sediment cannot be replaced. However, in a preliminary test with test strips information can be obtained as to the white cell content of the urine. Samples from patients in whom Addis count or sediment results showed no pathological leucocyturia, also had negative results in the test strip in a high percentage (84 out of 88 cases). A positive Cytur-test indicates lysed white cells in such cases (4 out of 88 cases). Due to the different sensitivity, as a consequence of a wider negative range, the Cytur-test resulted in fewer positive findings when compared to the other methods: 6 out of 24 in the Addis count and 2 out of 11 in urinary sediment.