A single parenterally administered dose of 2 gm of kanamycin sulfate cured 144 (93%) of 155 men with acute gonorrheal urethritis. No untoward side effects of the drug were encountered. In vitro sensitivity was determined for 67 isolates, for penicillin, kanamycin, streptomycin, and tetracycline, and an increase in resistance to penicillin and tetracycline is shown over the preceding 16 to 18 months for the Seattle-King County area. The authors consider culture of the sediment of a centrifuged, freshlyvoided urine specimen to be the most reliable criterion of cure. Prolonged observation of the results of treatment is unreliable because of the likelihood of reinfection. There is a great need for additional parenterally administered drugs effective in treating gonorrhea. Concurrent treatment of consorts is of critical importance in avoiding reinfection.