Background and Objectives: Patients attending sexually transmitted disease (STD) clinics are frequently screened for gonorrhea and chlamydial infection. To determine the efficiency of these screening efforts as a component of STD control, we evaluated treatment outcomes of patients with positive cultures who had not received presumptive treatment at their initial visit. Goals: To determine the treatment outcomes of patients screened for STDs who have positive test results. Study Design: Retrospective chart review of the computerized medical record. Results: Between January 1, 1994 and June 30, 1995, 24,823 patients were tested for gonorrhea, of whom 19.3% (4791) had positive cultures. Of patients with positive gonorrhea cultures, 564 (11.8%) had positive screening cultures and did not receive therapy at the time of evaluation. Similarly, screening chlamydial cultures were positive in 1539 (10.9%) of 14,162 patients screened for chlamydial infection. Forty-four percent (677) of these did not receive presumptive treatment for chlamydial infection at their initial visit. Overall, 20% of patients with positive cultures failed to return to the clinic for treatment within 30 days of screening. Of those who did return, 30% did so only after at least 2 weeks had elapsed. Conclusions: A substantial proportion of patients with positive screening tests for gonorrhea and chlamydial infection fail to comply with follow-up recommendations and thus are likely to remain infectious. Methods must be sought to enhance patient compliance with follow-up of test results and treatment if indicated.