In 2008, the US Centers for Disease Control and Prevention held the Chlamydia Immunology and Control Expert Advisory Meeting to foster a dialogue among basic scientists, clinical researchers, and epidemiologists studying genital Chlamydia trachomatis infection. The objectives of the meeting were to determine key questions related to C. trachomatis natural history and immunobiology, with implications for control programs;to review existing data on these key questions; and to delineate research needs to address remaining gaps in knowledge. The 9 articles in this supplement to The Journal of Infectious Diseases describe salient findings presented at the 2008 meeting, and this commentary summarizes and synthesizes these articles and discusses implications for chlamydia control efforts and future research priorities.