The clinical results of treatment of infravesical prostatic obstruction with an intraurethral coil in 150 consecutive patients are reported. A total of 80 patients had urinary retention and 70 had severe prostatism. Median observation time was 8.2 months, with a range of 0 to 40 months. In 75 patients the spiral was removed after a median of 4 months (range 0 to 30 months) because of planned prostatectomy in 17, urinary retention in 16, incontinence in 10, local discomfort in 7, no symptomatic improvement in 13 and causes not related to the spiral (stroke and so forth) in 7. Migration occurred 55 times in 42 patients but this only led to coil removal in 5. A total of 23 patients died with the coil in situ. Voiding symptoms improved considerably in the majority of the patients. Approximately two-thirds of the patients had no or few symptoms, while a fourth had moderate symptoms, leaving only approximately 10% with severe prostatism. Chronic bacteriuria was noted in 52 patients but was not a clinical problem. Calcification on the top and inside of the coil was noted mainly after long-term treatment, and probably necessitated exchange of the coil after 2 to 3 years. We conclude that the prostatic spiral is a useful alternative to an indwelling catheter. However, life-long followup is necessary in most patients.