There is great variability in different jurisdictions as to when and who undertakes investigations of deaths in custody and sometimes whether any investigation is done at all. In many jurisdictions, there is little awareness about the importance and relevance of a proper investigation of those deaths. Because a detainee has little freedom in many aspects of normal life, the detaining authority has to take on full responsibility for every detainee. Any death occurring in the hands of the detaining facility, and in the end, of the acting government or state or authority, should be fully and independently investigated in order 232to identify failings and learn lessons and to reassure the general public. This chapter identifies the key elements that should form the basis of all investigations following a death in custody. It has to be kept in mind that in many detaining facilities, violent deaths and self-inflicted deaths are much more frequent than in the general population (which may reflect management or personnel issues) and that even a natural death might still involve the responsibility of the detaining authority, which controls access to health professionals, medication, hygiene, and nutrition.