Newly synthesized viral RNA is transported out of the nucleus and translated, in the case of mRNA, or incorporated into new virions, in the case of genomic RNA. The gag and pol genes are encoded out of a frame on a single mRNA. Frameshifting during the translation of the viral gag-pol messenger RNA, therefore, is essential for the production of pol gene products (protease, reverse transcriptase, and integrase) (1). RNA secondary structure located downstream (3') from the gag/pol frameshift has been shown to be important for wild-type levels of frameshifting to occur (2). Compounds that either inhibit or alter viral mRNA frameshifting are potentially effective antiviral agents.