Sometimes, the cause of death can be found by simply looking at the corpse without opening it. In other cases, it may need to be opened, to find the cause of death. If it is opened, it is usually closed again; most of the time, corpses are buried. Before being buried, they are on display for some time. For this, they need to look acceptable. In certain cases, like when the corpse is opened, special permissions are perhaps necessary. These are usually given by the closest living relative, called next of kin.