This research on human-environmental transactions in small-scale prisons found that almost 40 percent of the prisoners expressed a dominant concern for freedom and that almost 30 percent of the identified niches were for freedom or autonomy. Such settings encourage equalitarian staff-prisoner communication, deemphasize formal disciplinary machinery, and are physically removed from sources of freedom restriction. Other features include enhanced mobility, the ability to choose or reject participation in activities, and the degree to which the setting reflects normal street life. Examples of such niches are farms, vocational training, and gardening crews. While the raw materials for the informal niche are available to all, formal niches exist for subpopulations with dramatic vulnerabilities and for those who cannot find a refuge within the mainline prison environment. Aged and invalid offenders often require a special niche which provides disengagement from other social groups, convalescent treatment, and a sense of community. Prisoners in such settings describe safety as a major source of satisfaction, along with the availability of medical care, a physical environment that recognizes the limits of old age, and friends with similar interests and values. Prisoners do not like aspects of the handicapped unit, fearing passivity and inactivity. Prison organization and practice do not recognize niche search and creation. However, a staff officer's awareness of environmental effects could help create more informal niches and ameliorate stress. The article includes 1 footnote and 28 references.