We compared data from two independent, representative samples of the US population to determine whether heterosexual adults 18 to 49 years of age modified their human immunodeficiency virus (HIV) risk behaviors between 1990/91 and 1992. We found little change in multiple sexual partnerships, having a risky partner, and HIV test seeking in the heterosexual population. Overall, consistent condom use significantly increased from 11% in 1990/91 to 20% in 1992, but this increase was limited to selected demographic groups. These results suggest a continuing need for HIV education among heterosexual adults.