The aim of this study was to screen healthy rural and urban Tanzanian men for chlamydial infection and gonorrhoea, and determine the prevalence and the predictive value of urethral symptoms, signs and pyuria. In 2 cross-sectional surveys, 796 men were interviewed regarding symptoms and examined for signs of urethritis. Gonorrhoea was detected by culture/Gram-stained smears, Chlamydia trachomatis by antigen immunoassay, and pyuria by leukocyte esterase dipstick test. The prevalence of chlamydial infection, gonorrhoea and pyuria among rural men was 9.6%, 0.4%, and 12.7%, and among urban bar workers 7.4%, 8.1% and 6.3% respectively. Among all, 0.6% had urethral discharge confirmed by examination, while 2.6% reported urethral discharge and 7.4% dysuria. Among chlamydiainfected men, 59 (89%) of the 66 cases did not have urethritis symptoms or signs. Similarly, 24 (88%) of 28 men with gonorrhoea were asymptomatic. Treatment based on the urethral discharge sign, would have detected only one out of 92 cases with gonorrhoea and/or chlamydia in these populations.