In generalized HIV epidemics, like Ethiopia, many infections occur within marital and cohabiting unions and the HIV-negative partners in discordant couples are at very high risk of contracting HIV if the couple does not take steps to protect the HIV-negative partner.The prevalence of HIV in urban population is high with high discordance rate (7.8%). Moreover early sexual initiation and premarital sex among youth is increasing, but use of protective measures such has condom and VCT is low. Although it is known that protection of uninfected partner is an acknowledged best practice in HIV prevention, it has not received much attention in the literature in determining magnitude especially among premarital couples in Ethiopia. Thus this book will have valuable importance to devise behavioral and other interventions for premarital couples especially for those sero-negative partners.It would lay basis for further biological and immunological studies to detail analyze determinant factors. Moreover,it contributes as a reference work for governmental,community-based and non-governmental organizations to address the problems of and develop appropriate programs.