IN AN ATTEMPT TO DEVELOP A TENTATIVE MODEL OF AGING IN PRISON, THE RESEARCHER USES A SAMPLE OF 40 OLDER PRISONERS, NONVIOLENT OFFENDERS, IN A LEXINGTON REGIONAL TREATMENT CENTER IN OKLAHOMA, A SEGREGATED MEDIUM SECURITY FACILITY, AND ANOTHER SAMPLE OF 55 VIOLENT AND NONVIOLENT OFFENDERS IN CUMMINS PRISON IN ARKANSAS, AN INTEGRATED MAXIMUM SECURITY INSTITUTION. IT IS SIGNIFICANT THAT PRISONERS FROM TWO SEPARATE SOCIAL ENVIRONMENTS AS WELL AS PRISONERS WITH DIFFERENT CRIMINAL CLASSIFICATIONS ARE USED. NO CONTROL GROUP IS USED. QUESTIONNAIRES ARE ADMINISTERED COVERING SOCIODEMOGRAPHIC DATA, THE OLDER PRISONER'S REFERENCE GROUP, INSTITUTIONAL DEPENDENCY AS SHOWN BY GROUP INTERACTION AND PERCEPTION OF LIFE ON THE OUTSIDE, LIFE SATISFACTION, ACTIVITIES, AND THE PRISONERS' CORRECTIONAL HISTORY. QUANTITATIVE FINDINGS ARE PRESENTED IN DESCRIPTIVE AND TABULAR FORM. IT IS FOUND THAT THE VARIABLES OF MARITAL STATUS, LENGTH OF IMPRISONMENT, AND DIFFERENCES IN CRIMINAL CLASSIFICATION TEND TO SUPPORT THE MODEL OF INSTITUTIONAL DEPENDENCY. HOWEVER, THE INFLUENCE OF SOCIAL STRUCTURE OF THE PRISON DID NOT EMERGE AS A SIGNIFICANT FACTOR. LIKEWISE, PERCEIVED HEALTH STATUS FAILED TO SHOW A POSITIVE RELATIONSHIP WITH INSTITUTIONAL DEPENDENCY. QUALITATIVE FINDINGS ARE DETERMINED BY INTERVIEWS WITH STAFF AND INMATES AND ALSO BY OBSERVATION. INMATES THEMSELVES CHARACTERIZE INSTITUTIONAL DEPENDENCY AS LACK OF A PARTICULAR REFERENCE GROUP ON THE OUTSIDE AFFECTED BY THE LENGTH OF IMPRISONMENT RATHER THAN BY THE NATURE OF THE SOCIAL STRUCTURE. OTHER FACTORS ARE EXPLORED AS TO THEIR RELATIONSHIP TO INSTITUTIONAL DEPENDENCY: THE TIME OF FIRST IMPRISONMENT, WHETHER A CHRONIC OFFENDER, THE THERAPEUTIC VERSUS THE CONVENTIONAL PRISON, AND LIFE SATISFACTION OF OLDER PRISONERS IN A THERAPEUTIC PRISON VERSUS LIFE SATISFACTION OF THOSE IN A CONVENTIONAL PRISON ENVIRONMENT. REFERENCES FOR THIS STUDY INCLUDE BOOKS ON PENOLOGY, GERONTOLOGY, AND OLDER OFFENDERS. THE APPENDIX CONTAINS THE SURVEY INSTRUMENTS USED, THE QUESTIONNAIRE, THE INSTITUTIONAL DEPENDENCY INDEX, A LIFE SATISFACTION INDEX, ALSO SECTIONS DEVOTED TO DEMOGRAPHIC DATA AND CORRECTIONAL HISTORY. (FCW)