A review is presented of infections in the female genital tract caused by Chlamydia trachomatis. C. trachomatis primarily infects the cuboidal epithelium of the cervix. Chlamydial cervicitis is four to six time more common in Europe than gonococcal cervicitis. The infection is sexually transmitted and can cause urethritis in the male, endometritis and salpingitis in the female as well as infections in the neonate. The risk of salpingitis in women with chlamydia cervicitis has been estimated to be about 1:10, i.e. the same as for gonorrhoea. Chlamydial cervicitis is asymptomatic in about half of the culture-positive cases. A correlation between colposcopic follicular cervicitis and the isolation of C. trachomatis has been reported. Examination of serum specimens for IgG antibody to the organism is of little use for the diagnosis of cervicitis. Treatment with macrolide antibiotics or tetracyclines eradicates the organism.