We will undertake a prospective study of genital herpes infection of 7,000 women recruited from five family planning clinics in the metropolitan Pittsburgh area who are receiving long term care in contraceptive services and genital health. Patients will be recruited over a two year period and followed for three years for serum antibodies against herpes simplex types 1 and 2, and for symptomatic genital herpes infection. Those who are seropositive for HSV-2 will get annual vaginal cultures to detect asymptomatic genital virus shedding. All cases of primary or recurrent genital herpes disease will be seen in the clinics. Specimens for virus culture and serum antibody will be obtained to document these episodes and their effects on antibody titers. Patients will be followed for the duration and frequency of their episodes. We will obtain from these data specific incidence rates for symptomatic or inapparent infection with HSV-1 and HSV-2. We will know how many patients with antibody against HSV-2 have symptomatic disease or asymptomatic shedding. The influence of demographic characteristics and prior antibody status on the acquisition of infection will be analyzed. In addition, we will conduct a nested case controlled study. For each index case with primary disease or who is having an initial recurrence, a control will be selected who is matched for antibody status, age, socio-economic status, marital status and clinic. The disease episode will be analyzed for risk factors and precipitating factors. Some such factors are exposure to partners with genital or oral herpes, type of sexual practice, contraceptive practices, socio-economic status, physiologic factors such as menstration, and psychological stress. Using the Peri Life Events Scale, we will measure psychological and environmental stress as a precipitating factor. the index cases and controls will also be followed by serology to elucidate the relationship between recurrences and change in antibody titers to HSV-2.