The questions asked for this survey were intended for all respondents, including witnesses directly experienced in PPC, guards, camp officers and their families. As level of their experience differs, however, some questions were asked only to the applicable respondents and some questions were waived from the respondents who refused to answer or were nervous with revealing identification or with particular situations. (2) Scope and Content of Survey on Disappearances This survey also contains cases of missing persons who are believed to have some connection with PPC. For this purpose, questions were also asked about cases of disappearance during the in-depth interviews under the present survey. The survey of witnesses to disappearance was conducted at the same time with the survey on PPC. Questions were asked about witness to missing persons, occurrence of missing cases, the circumstance under which a person was missing and witness’s understanding of the missing case to 17 persons through in-depth interview and 322 North Korean defectors who arrived in South Korea in 2009. In-depth interviews were focused on the family of the missing persons or witnesses to the case of disappearance. The results of the analysis of indepth interviews is presented in integration with PPC as the two subjects are linked. For the purpose of survey on cases of disappearance, the researchers of the present survey obtained completed questionnaire from 322 North Koreans who arrived South Korea in 2009. Main questions asked were as follows: 27