Book excerpt: One in five people in the United States had a sexually transmitted infection (STI) on any given day in 2018, totaling nearly 68 million estimated infections. STIs are often asymptomatic (especially in women) and are therefore often undiagnosed and unreported. Untreated STIs can have severe health consequences, including chronic pelvic pain, infertility, miscarriage or newborn death, and increased risk of HIV infection, genital and oral cancers, neurological and rheumatological effects. In light of this, the Centers for Disease Control and Prevention, through the National Association of County and City Health Officials, commissioned the National Academies of Sciences, Engineering, and Medicine to convene a committee to examine the prevention and control of sexually transmitted infections in the United States and provide recommendations for action. In 1997, the Institute of Medicine released a report, The Hidden Epidemic: Confronting Sexually Transmitted Diseases. Although significant scientific advances have been made since that time, many of the problems and barriers described in that report persist today; STIs remain an underfunded and comparatively neglected field of public health practice and research. The committee reviewed the current state of STIs in the United States, and the resulting report, Sexually Transmitted Infections: Advancing a Sexual Health Paradigm, provides advice on future public health programs, policy, and research.