Pipe bombs are crudely constructed improvized explosive devices which are easily made at home. They are increasingly used by terrorists and others, and may inflict serious injuries and cause death. Four fatalities have occurred in association with their use in Northern Ireland between 1998 and 2002. In 2 cases, death was due to penetrating shrapnel injuries to the chest causing laceration of the great vessels, and a third fatality occurred due to a bomb fragment penetrating the cranial cavity. A pipe bomb exploded close to the back of the head of a fourth victim and this was associated with a severe brain injury. The pathologist was able to determine the position of the victim in relation to the explosion by interpreting the pattern of injuries. It seems likely that 2 of the victims had been involved in the construction, transport, or use of the devices. A third victim was entirely innocent and had been in the process of removing a pipe bomb, which had been thrown through the window of her home, when it exploded. The fourth victim was a member of the security forces who had been struck by a bomb fragment, in the region of the right eye, during a period of sectarian unrest.