This volume presents an integrated epidemiologic, social, and economic analysis of the global epidemics of HIV among sex workers in low- and middle-income countries. The book provides a comprehensive review and synthesis of the available public health and social science data to characterize the nature, scope, and complexities of these epidemics. A community empowerment-based approach to HIV prevention, treatment, and care is outlined and demonstrated to be cost-effective across multiple settings, with a significant projected impact on HIV incidence among sex workers and transmission dynamics overall. The Global HIV Epidemics among Sex Workers seeks to assist governments, public health implementing agencies, donors, and sex worker communities to better understand and respond to the epidemics among a population facing heightened social and structural vulnerabilities to HIV. The book combines a systematic review of the global epidemiology of HIV among sex workers and in-depth case studies of the epidemiology, policy and programmatic responses and surrounding social contexts for HIV prevention, care and treatment in eight countries. The authors employ mathematical modeling and cost-effectiveness analysis to assess the potential country-level impact of a community empowerment-based approach to HIV prevention, treatment, and care among sex workers when taken to scale in four countries representing diverse sociopolitical contexts and HIV epidemics: Brazil, Kenya, Thailand, and Ukraine. In each setting, greater investment in prevention, treatment, and care for sex workers is shown to significantly reduce HIV. Together these findings underline the urgency of further global investment in comprehensive, human rights-based responses to HIV among sex workers.