Despite ongoing evidence that one quarter of HIV-infected people in the United States are unaware of their infection, widespread implementation of the Centers for Disease Control and Prevention's 1993 recommendations regarding routine inpatient HIV testing has not occurred. This study compares two HIV testing strategies: the initial phase of inpatient HIV testing (1999-2001) utilized a physician-referral-based system. The second phase (2001-2003) included the first 2 years' experience with having trained HIV counselors directly approach inpatients regarding their willingness to undergo voluntary HIV counseling and testing (VCT) without physician referral. This latter phase was prompted by a patient attitude survey demonstrating favorable responses to unsolicited approaches by staff regarding HIV testing. Barriers to implementing the latter strategy are discussed and initial experience with rapid HIV testing on this service is also presented. Referral-based testing yielded 2.3 patient referrals (6.4% of total admissions) resulting in 1.2 HIV tests and 0.7 counseling only sessions per day. Nonreferral based testing resulted 6.2 HIV tests and another 3.0 counseling-only sessions per day. HIV VCT on an inpatient service is feasible but challenging. Most patients respond favorably to being approached for VCT. Routinely offering HIV tests to inpatients yields higher testing rates than physician referral-based systems and increases the number of patients who know their HIV status. Recommendations for implementing routing HIV testing on an inpatient service are made.