The occurrence of acute pelvic inflammatory disease (PID) caused by Chlamydia trachomatis could be reduced if chlamydial screening were more widely instituted, but financial support for such programs remains limited. Logically, the agencies that could most cost-effectively fund screening programs are those that benefit most from reduction in costs incurred by PID. Therefore, the authors retrospectively analyzed charges for 630 women with acute PID presenting to a county hospital over a 2-year period. Sixteen per cent of patients required hospitalization. Of the total charges, 54% were not paid by any agency, 18% were paid by the county, and 22% by the state. A computer model was developed for analysis of screening programs in high-risk women (prevalence, 17%). The savings in charges for acute cases of PID alone did not make it cost-effective for any single agency to fund chlamydial screening. However, the model showed that it would be cost-effective for the county and the state jointly to fund a screening program using a direct antigen test costing under $7 per test.