This book is derived from a research study entitled "Assessment of the Relationship between Religiosity and Sexual Behaviour among Unmarried Adolescents in selected Schools in Lusaka Zambia". It has been written to support policy makers, scholars and programme implementers in mitigation of HIV transmission. The purpose is to create awareness on facts that will contribute to a body of knowledge to be used to develop strategies in HIV prevention in health systems. One of the societal relevance is to contribute towards the search of responses to questions that are often asked by the society at large in pursuit to solve HIV problems. Understanding measures of preventing HIV transmission will entail devising strategies intended to reduce incidences of HIV infection. This will benefit a number of stakeholders such as students, lecturers, policy makers, communities and the nation as a whole to foster positive decision making on adolescents in order to maintain healthy standards and become responsible citizens. The long term effect will be change of mind set among adolescents on sexual behaviour, reduction of HIV infection, STIs, unintended pregnancies and forced early marriages.