One hundred and fifty women who attended a genitourinary medicine clinic and who required a speculum examination were investigated to determine the association between Chlamydia trachomatis and urethral symptoms and signs. Those who had taken antibiotics with anti-chlamydial activity within 3 months or those who were menstruating, pregnant or using an intrauterine contraceptive device were excluded. C. trachomatis infection of the urethra, or infection of the urethra and cervix together, combined with each separately, were strongly associated with > = 5 polymorphonuclear (PMN) leucocytes per high-power field (x 1000) in a Gram-stained urethral smear (P < 0.00005 and P < 0.0005, respectively). This appeared not to arise from leucocyte contamination from the lower genital tract. However, C. trachomatis infection of the urethra was not associated with symptoms of dysuria or frequency. In conclusion, it seems likely that C. trachomatis infection of the urethra in women probably causes urethritis which is usually asymptomatic. Women who have objective evidence of urethritis might best be managed by appropriate antibiotic therapy and counselling, and advice that partners should attend for review.