Following a brief historical overview of in-prison drug treatment programs in the United States, Inciardi focuses on in-prison drug treatment inaugurated in Delaware in the late 1980s. A program called "The Key" was established as a therapeutic treatment community in a Delaware men's maximum-security facility. Inmate participants/residents lived separately from the inmate general population under a treatment regimen that focused not only on drug abuse but criminogenic needs generally. In order to be eligible for participation, inmates had to be within 18 months of their scheduled release, so they would transition from the treatment community into the community without having to reenter the inmate general population. Another aspect of the transition is participation in Crest Outreach Center a community-based work release facility that monitors drug use through self-reports and drug testing. Subsequent to the establishment of the men's program, a similar program for women, called the CI Village was started in a facility in New Castle, DE. Evaluation of these programs has involved an assessment of drug use and arrests at 6 months and 18 months after release from prison. These data were obtained for four groups: A comparison group that did not participate in either The Key or the Crest Outreach Center; participants in only The Key program, but not the Crest program; participants in only the Crest program, but not The Key program; and participants in both The Key and the Crest programs. Participants in both The Key and Crest programs performed better than the other groups at both 6 months and 18 months.