This is a collaborative piece of work undertaken between the PCA and a Principal FME. The study is based on 16 cases of internal drug concealment drawn from 43 drug-related deaths in custody in England and Wales between 1997 and 2002. These data are supplemented by three case studies from a county force involving non-fatal drug concealment to illustrate practical custody issues. The majority of the 16 deaths were white (n = 12) and male (n = 13) with a mean age of 34 years. In half of the cases, the deceased was known or believed to have concealed drugs orally at the point of initial contact with police. In 4/16 cases, the individual first showed signs of medical distress in a public place, a further 4 collapsed on arrival at the police station and two more detainees were subsequently found collapsed in their cell. Drug toxicity was the most common cause of death (10/16). In 5 cases death was caused by airway obstruction by swallowed packages. Both cocaine (14/16) and cannabis (8/16) traces were found in post-mortem samples. The report emphasises the need for a safety first approach.