By 1865, elements of the original penitentiary design based on regimentation, isolation, religious conversion, and steady labor had been subverted by pervasive overcrowding, corruption, and cruelty. Despite prison deficiencies and appeals of several prison reformers, most prisons were overcrowded and few observers were ready to abandon the existing system of incarceration. The Elmira Reformatory in New York represented an exception in that the focus was on rehabilitation and education. Nonetheless, the reformatory movement of the 1870's did not halt the deterioration of American prisons. At the beginning of the 1900's, psychiatric interpretations of social deviance began to assume a central role in criminology. Other progressive criminologists proposed the social learning model as a way of justifying broad discretion in sentencing practices and sought alternatives to imprisonment. Liabilities and assets of the prison reform movement are evaluated, the emergence of the Federal prison system is considered, and prison system developments after World War II are noted that concern rehabilitation and prisoner rights. References and photographs