-58 of vulnerability, are an important source of information not only on the specific situation of the complainant, but often also on structural problems with vulnerability. In addition to the complaints, it is usually informative to check the case-law where available, in particular cases concerning the use of preventive or compensatory remedy against inhuman and degrading treatment by the detainees of the respective institution. Meeting or otherwise receiving information from other stakeholders, even where their interest is not specifically the rights of the detainees, may prove beneficial. These include relatives who visit their imprisoned family members, lawyers, representatives of religious denominations, service providers and employers. Media reports should also be taken into consideration. Non-governmental organizations committed to the rights of vulnerable groups may be very useful to consult before the visit, even if they do not collect information on such groups and individuals in detention. They are an invaluable source of information on the specific vulnerability of such persons, and on the social attitudes which may be instrumentalized in abusive behaviour. In some cases, e.g. with persons suffering from different forms of disability, such NGOs may provide information on the appropriate accommodation and rehabilitation of such detainees. 3.3.3. Monitoring principles Monitoring principles are fundamental value statements, which guide the behaviour of the monitoring team by underlying its strategy of action and its approach to fact-finding. Different authors propose a different number of principles, ranging from 492 to 17.93 Here we can restrict ourselves to six. 1. Do no harm. This is perhaps the most important of all monitoring principles. In essence, it means that human rights monitoring should not aggravate the condition of the victims in any way. Informationgathering for monitoring purposes can never outweigh the victim’s safety. Therefore, the monitors should take all precautionary measures to ensure that their work in its entirety does not cause further damage to the victims. 92. Amnesty International and CODESRIA, UKWELI: Monitoring and Documenting Human Rights Violations in Africa, Dakar, 2000, pp. 29-46. 93. The Advocates for Human Rights, A Practitioner’s Guide to Human Rights Monitoring, Documentation and Advocacy, Minneapolis: AHR, 2011, pp. 15-17.