Risk assessment is important for two reasons. In countries where there is a low HIV prevalence, risk assessment helps determine who is most appropriate to target for counseling and testing. It is also important on an individual basis to identify specific risky behaviors in order to provide effective risk reduction counseling. The factors listed here help identify individuals who may be at increased risk for HIV infection. Young single men and women are likely to be at increased risk because of greater frequency of unprotected sexual activity and increased likelihood of multiple partners. Young women may also be more vulnerable to HIV for physiologic reasons, such as increased rates of cervical ectopy. Studies have demonstrated that women whose husbands are long-distance truck drivers or are in the military are at increased risk because their husbands are more likely to have had contact with commercial sex workers. Similarly, when a population is unstable because or war or famine, families may be separated and unsafe sexual practices are more common. Certain specific sexual behaviors, signs or symptoms or history of a sexually transmitted infection in the woman or her partner, and a current or past history of injection or noninjection drug or alcohol abuse indicate individuals at increased risk of HIV who should receive individualized counseling and be offered voluntary HIV testing. Active tuberculosis is more common in HIV-infected persons and is an indication for HIV testing. Pregnant women are a priority for counseling and voluntary testing because of greater availability of effective short-term antiretroviral therapies to reduce the risk of mother-to-child transmission. Finally, any individual who has symptoms such as unexplained weight loss, chronic diarrhea , fevers of unclear cause, or oral thrush should be offered HIV testing since these symptoms may indicate the presence of underlying HIV disease.