In April 2002 an accident involving an industrial radiography source containing Ir-192 occurred in Cochabamba, Bolivia, some 500 km from the capital, La Paz. The source, in a remote exposure container, remained exposed within a guide tube, although this was not known at the time. The container, the guide tube and other equipment were transported from Cochabamba to La Paz as cargo on a passenger bus. This bus had a full load of passengers for most of the eight hour journey. The equipment was subsequently collected by employees of the company concerned and transferred by taxi to the company's shielded facility. This publication gives an account of the event, the doses received and the medical assessment. It also presents information relevant to national authorities and regulatory organizations, emergency planners and a broad range of specialists, including physicists, radiation protection officers and medical specialists. It is hoped that dissemination of the information contained in the report will help reduce the likelihood of similar accidents occurring or, if they do occur, help mitigate their consequences