To assess the trend in acceptance of human immunodeficiency virus counseling and testing (HIV-CT) among clients attending a public sexually transmitted disease (STD) clinic, 13,139 clients who visited the largest STD clinic in Oregon at least once from 1989 through 1995 were investigated. Overall, 6236 (47.5%) of the clients accepted HIV-CT, and 98 (0.7%) clients reported having previously tested positive for HIV infection. The proportion of clients accepting HIV-CT increased from 28.2% in 1989 to 60.1% in 1995 (trend: p < 0.001). Among those who had never tested for HIV, acceptance of HIV-CT increased from 28.4% in 1989 to 60.9% in 1995 among HIV-uninfected clients (trend: p < 0.001) and from 20.6% in 1989 to 43.8% in 1995 among HIV-infected clients (trend: p = 0.13). The proportion increased from 25.9% in 1989 to 59.4% in 1995 (trend: p < 0.001) among those who previously tested negative for HIV and from 8.3% in 1989 to 25.0% in 1995 (trend: p = 0.03) among those who previously tested positive for HIV. Increases were seen in both sexes across all age and racial or ethnic groups. Acceptance of HIV testing increased among gay or bisexual men from 29% in 1989 to 57% in 1995 (trend: p < 0.001), and among IDUs from 49.5% to 78.8% (trend: p < 0.001). We conclude that HIV-CT is becoming more acceptable among public STD clinic clients, although extra efforts must be made to reach the clients who know they carry the virus but continue to practice unsafe sex.