At the end of 2005, approximately 7 million people (or 1 of every 33 American adults) were either in jail, in prison, or on parole. Compared with the general public, newly incarcerated inmates have an increased prevalence of human immunodeficiency virus infection, hepatitis B virus infection, hepatitis C virus infection, syphilis, gonorrhea, chlamydia, and Mycobacterium tuberculosis infection. While incarcerated, inmates are at an increased risk for the acquisition of blood-borne pathogens, sexually transmitted diseases, methicillin-resistant Staphylococcus aureus infection, and infection with airborne organisms, such as M. tuberculosis, influenza virus, and varicella-zoster virus. While incarcerated, inmates interact with hundreds of thousands of correctional employees and millions of annual visitors. Most inmates are eventually released to interact with the general public. Tremendous opportunities exist for infectious diseases specialists and infection-control practitioners to have an impact on the health of correctional employees, the incarcerated, and the communities to which inmates return. This article presents a brief review of some of the most important infection-control challenges and opportunities within the correctional setting.