The primary way of preventing HIV infections is to change behaviors that enable transmission of the virus specifically those behaviors relating to sex and drug injection. Realistic public health workers have focused on encouraging adoption of safer sexual practices primarily condom use. The fundamental way to persuade people to engage in preventive practices is through targeted education aimed at particularly at-risk communities. Other effective behavioral interventions against HIV infections are: testing and follow-up counseling; comprehensive sex education; peer influence and community action; advertising and marketing; easing access to condoms; physician-patient dialogue; drug treatment; access to clean needles; and direct outreach. On the contrary interventions that do not work are the following: one-time exposure to information; delivering a single message; abstinence-only programs; and coercive measures to identify people with HIV or their sexual partners.