The two main theories of reformation are the medical model, which assumes that most prisoners have personality defects, and the reconditioning model, which assumes that the causes of criminality are mainly in society itself. An alternative and more tenable model is an educational growth model. It assumes that delinquents and criminals have deficits in certain analytic problem solving skills and in certain interpersonal and social skills that are required to function in straight society. It also views the delinquent or criminal as a decisionmaker rather than as a victim or pawn. The model views the primary tasks of penitentiaries as habilitation and security, with habilitation through education the first priority. Traditional prison settings lack any of the elements of experience required for intellectual, social, and moral growth. Strategies should maximize the separation of programs aimed at habilitation so that they are not identified with the day-to-day operation of the prison. Prisoners who were students in several prisons in Canada, the United States, and Great Britain in 1974-75 evaluated the effectiveness of various educational programs. The responses indicated that programs emphasizing discussion of social, political, and ethical issues or developing problem-solving and interpersonal skills produced significant intellectual social, and moral growth. An educational program, especially if provided by mature instructors from outside the prison, can thus improve skills which have been previously undeveloped in the delinquent and criminal. The educational programs represented the acculturation of the delinquents or criminals. Similar programs in high schools might develop better citizens and reduce criminal activities. Thirty-two references are listed.