747 consecutive patients, 531 men and 216 women, attending the Division of Dermatovenerology, City Health Dept., Oslo, were screened for N. gonorrhoeae (14.5% and 18.5%), C. trachomatis (19.6% and 20.8%), G. vaginalis (0.2% and 6.5%), and C. albicans (1.1% and 21.3%). The prevalence is given in brackets for men and women, respectively. This study was undertaken in order to determine the relative prevalence of these microorganisms with particular reference to G. vaginalis, to determine the importance of concomitant infections, and the possible effect of contraceptive methods (oral contraceptives and IUD) on the prevalence of these microorganisms.