A profile of the Ossining Correctional Facility covers its history, physical layout, role in the State correctional system, and security staff organization. Inmates and staff alike were predominantly black and Hispanic from urban areas, and the facility had become the workplace of young, inexperienced guards who often applied for transfer the day they arrived. Diverse sources of information on conditions at Ossining revealed a consistent picture of fire hazards, heating and ventilation problems, very poor sanitary conditions, shortages in winter clothing for inmates, deficiencies in medical care, an unusually high death rate, security problems, and escalating inmate violence. All were exacerbated by overcrowding. Inmates persistently complained that they remained in transient status for several months. Other problems concerned inmate idleness, few recreational activities, prison policies on mail and packages, alleged guard corruption, no educational programs, restricted space for visitors, denying inmates access to the law library, and dissatisfaction with inmate grievance procedures. Extensive construction and renovation over the past 2 years also contributed to Ossining's disorganization and turbulence in January 1983. The report chronicles the events of the disturbance, covering staff and inmates' characteristics, the guard's actions which precipitated an incident, correctional system's response, negotiation, retaking the cell block, the union reaction, and the legislature's response. It assesses reports about drunken inmates and drunken guards starting the riot and official accounts of inmate injuries. The study concludes that there is no simple explanation of why the uprising occurred, but Ossining, like many other New York State prisons, was a troubled institution before the disturbances and has many problems needing immediate correction. The appendixes include tables, organizational charts, regulations, a chronology of early warning reports, and descriptions of some individual inmates.