The case of specimen collection has led to the suggestion that urine might be a useful specimen for the isolation of sexually transmitted disease agents. It would only be an appropriate specimen for agents that infect the urethra, such as Neisseria gonorrhoeae or Chlamydia trachomatis. Comparative tests have shown that culture of urine for chlamydiae (from men with urethritis) or for gonococci from women is an insensitive procedure. Gonococci can be isolated from urine from men at rates essentially equivalent to culture of urethral swabs. If specimens can be processed promptly (to avoid bactericidal effects of urine), culture of urine can likely be useful for screening asymptomatic men for gonococcal infection.