The number of individuals infected with human immunodeficiency virus (HIV) and other pathogens causing sexually transmitted diseases (STDs) is growing dramatically worldwide. Globally, heterosexual transmission may account for as much as 85-90% of new cases of HIV infection. Latex condoms represent an effective barrier against sexually transmitted pathogens, but unfortunately, their use is not generalized. Therefore, there is an urgent need to develop safe and potent topical microbicides under the control of women to efficiently reduce the spread of sexually transmitted infections. Sodium lauryl sulfate (SLS), an anionic surfactant with protein denaturing potency, is a potent inhibitor of the infectivity of several enveloped (Herpes simplex viruses, HIV- 1, Semliki Forest virus) and nonenveloped (papillomaviruses, reovirus, rotavirus and poliovirus) viruses. The mechanism of action of SLS involves the solubilization of the viral envelope and/or the denaturation of envelope and/or capsid proteins. Studies have shown that SLS is not toxic for cultured cell lines of different origins at concentrations that inactivate HIV-1, herpes and human papillomavirus in vitro. In addition, intravaginal pretreatment of mice with a gel formulation containing SLS, completely protected animals against Herpes simplex virus type-2 infection. The gel formulation containing SLS was also well-tolerated following repeated intravaginal administrations to rabbits. Taken together, these data suggest that SLS represents a potential candidate for the use as a topical microbicide to prevent the sexual transmission of HIV-1, herpes, human papillomavirus and possibly other sexually transmitted pathogens. The impact of such a preventive tool on public health can be enormous.