The senior consultant and senior health adviser in all genitourinary medicine clinics in the UK were sent a questionnaire on HIV testing practice in seven clinical scenarios. For each scenario the recommended time interval between possible exposure and final HIV antibody test varied from a minimum of 3 months to a maximum of over 5 years. The results show 2 broad patterns: when the contact was not someone known to be HIV positive the commonest recommended time interval was 3 months; for a known exposure to HIV the commonest recommendation was 6 months. Only 16 out of the 151 clinics replying had a written policy setting out the interval to elapse between possible exposure to HIV and the final test for HIV antibodies. Variation of practice within clinics is less where written policies exist. Some staff in clinics are recommending inappropriately long intervals before the final HIV test.