Prison work is one of the important treatments designed for the reform and social rehabilitation of inmates. The primary purpose is to nurture inmates' willingness to work, teach them vocational knowledge and skills, and develop their endurance and concentration. The forms of prison work are divided, according to their nature and purpose, into production work, vocational training, and work for sustaining the institution. The latter includes work needed for sustaining the operations of the institution, including cooking, laundry, and cleaning (maintenance work), and work needed for construction work under direct management such as maintenance of the institution (building and repair work). There are 7 categories in the production work, including woodwork, printing, tailoring, and metalwork. Inmates are assigned to work in accordance with their individual aptitudes. Outside work is also carried out. This includes work undertaken in outside work sites under the management of the prison and other work undertaken in ordinary work sites with the cooperation of private sector companies. There are 2 forms of working, "residential work" for which inmates stay overnight at the work site and "commuting work" for which inmates travel to the work site from the penal institution. Inmates are mainly engaged in agriculture or livestock farming, woodwork, metalwork, or shipbuilding, etc.
  Prison work is mainly carried out by inmates sentenced to imprisonment with labor and inmates in workhouses, who are obliged to engage in prescribed work under the Penal Code. In addition, some voluntary work is also undertaken by inmates sentenced to imprisonment without labor, inmates awaiting trial and others, who are not obliged to engage in prescribed work under the Penal Code. As of March 31, 2002, 89.3% of the inmates sentenced to imprisonment without labor and 10.7% of the inmates awaiting trial were engaged in voluntary work (Source: Correction Bureau, Ministry of Justice).

  The working hours of working inmates are 8 hours per day and 40 hours per week, with Saturdays and Sundays off, as a rule. To improve the working environment, labor safety and health, measures are taken in line with the principles of the Labor Standards Law, the Industrial Safety and Health Law, and others.
  In FY 2001, the average daily number of inmates engaged in prison work was about 50,300, and the amount of revenue from prison work was about ¥9.2 billion (Source: Correction Bureau, Ministry of Justice).
  All revenue from prison work becomes national revenue. However, a work remuneration is paid to those engaged in the work. The work remuneration is paid as benevolence or encouragement rather than a wage for labor, and it is in principle paid upon release. The (estimated) average monthly work remuneration per inmate in FY 2001 was ¥4,215 (Source: Correction Bureau, Ministry of Justice).
  Inmates are also allowed to engage in personal work completed in their spare time under certain conditions to yield income. As of March 31, 2001, 95 inmates were engaged in such work, yielding an average monthly income of ¥5,297 (Source: Correction Bureau, Ministry of Justice).

  Vocational training is designed to teach inmates the skills needed for vocations or to improve their already-acquired skills. There are 3 forms of training, namely general training, group training, and internal training. Inmates receive technical training that is aimed to enable them to obtain official qualifications, license or advanced skills as well as standard training that is aimed to enable them to acquire vocational skills that will help them achieve smoothly social rehabilitation.
  Vocational training is given on 53 topics, including welding, electrical engineering, car maintenance, construction, plate making/printing, woodcraft, construction machinery, and nursing services. In FY 2001, 1,671 inmates completed vocational training, while a total of 1,657 inmates obtained qualifications or licenses as welding technicians, electricians, boiler operators, and so forth (Source: Correction Bureau, Ministry of Justice).