Revision with unchanged content. This book examines the incidence rates of sexually transmitted infections (STIs) among minority group teenagers in the United States and among adults in the United States and China. The focus is on general trends and patterns in the US compared to those in China. Research questions include whether or not the early onset of sexual activity is directly related to the incidence of STI transmission among Americans. Additionally, analyses of the Chinese population address the question of whether or not a hidden epidemic exists with regard to STI transmission rates. The data analysed offer unique insights as they contain information on sexual behaviour for both populations as well as urine results for the Chinese. Results are presented in descriptive tables and through the use of logistic regression. It is important to study these trends within the U.S. and abroad in China for many reasons. These include lifelong difficulties and complications such as loss of fertility. Furthermore, STI infection amplifies the transmission rate of HIV/AIDS and should be studied specifically for this reason, if none other.