Probationary supervision is designed to instruct offenders and juvenile delinquents to observe certain conditions while leading normal lives as well as to provide them with necessary guidance and support, with the aim of assisting them in reforming and rehabilitating themselves.

  The types of parolees and probationers and respective periods of probationary supervision are as follows:
(i) Juvenile probationers (juvenile offenders placed on probation by a decision of a family court)
  In principle, the period of probationary supervision shall be from the date of decision of probation until the probationer's 20th birthday. In the case of a probationer already over 18, the period shall be 2 years from the date of decision.
(ii) Juvenile parolees (juveniles granted provisional discharge from juvenile training schools)
  In principle, the period of probationary supervision shall be from the date of provisional discharge from the juvenile training school until the parolee's 20th birthday.
(iii) Adult parolees (inmates granted parole from penal institutions
  In principle, the period of probationary supervision shall be from the date of parole until the remainder of the penal sentence expires.
(iv) Adult probationers (offenders given suspended sentence on condition of probation)
  The period of probationary supervision shall be from the date of final decision until the period of suspension of sentence expires.
(v) Women's guidance home parolees (women granted provisional discharge from women's guidance homes)
  The period of probationary supervision shall be from the date of provisional discharge from the women's guidance home until the remainder of the guidance disposition period expires.

  Treatment on probationary supervision is usually carried out cooperatively by a probation officer and a volunteer probation officer for a single probationer or parolee. The Japanese probation system is characterized by such collaborative nature in which the expertise of probation officers is organically combined with the local and nongovernmental character of volunteer probation officers.
  Probation officers clarify problem areas with respect to probationary supervision, establish guidelines in implementing probationary supervision, and design treatment plans at the beginning of the probationary supervision, based on interviews with parolees and probationers and relevant records on them. Volunteer probation officers provide guidance and support for parolees and probationers and their family members by contacting them directly through interviews and home visits, in line with such treatment plans. The progress of such treatment is reported by volunteer probation officers to the probation office every month. In response, probation officers, while maintaining contact with volunteer probation officers, take measures to address changes in the situation, such as interviewing probationers and parolees and related parties if necessary.
  Probation officers are stationed in prescribed locations such as municipal public institutions or halfway houses in the area where the parolee or the probationer resides (regular stationing). Using such location as a base, they actively and efficiently carry out interviews with parolees and probationers and their family members, make home visits, and contact and hold discussions with volunteer probation officers as well as related organizations and associations. Furthermore, probation officers interview parolees and probationers from evening into the night, or stay in halfway houses and interview them.