During a 28-month interval 70 spinal cord injury patients in the initial rehabilitation hospitalization underwent 5,052 days of intermittent catheterization. Intermittent catheterization was done with a sterile technique and a neomycin-polymyxin irrigant. At the time of transfer to our facility 39 patients were using Foley catheter drainage but no difficulty was encountered when these patients were changed to intermittent catheterization. While on intermittent catheterization 52 urinary tract infections occurred, half caused by gram-positive cocci, 24 by gram-negative bacilli and 2 by Candida albicans. These infections occurred in 38 patients (54 per cent) at an over-all rate of 10.3 infections per 1,000 patient-days of intermittent catheterization. Only 2 infections were symptomatic and these occurred in patients on pass who unilaterally discontinued intermittent catheterization. Only 6 infections were not cured by antimicrobial therapy. Urinary tract infection was less common in patients who had incomplete spinal cord injuries. Infections caused by organisms susceptible to the irrigant containing neomycin-polymyxin occurred almost exclusively in patients catheterized 3 or fewer times daily. Infection was rare after 3 months of intermittent catheterization. Intermittent catheterization with our technique poses little infection hazard and can be introduced readily in acute spinal cord injury patients before transfer to specialized facilities.