This publication brings together in a more convenient format the official records and other relevant publications relating to the negotiations on the "Amendment to the Convention on the Physical Protection of Nuclear Material". The Amendment makes it legally binding to protect nuclear facilities and material in peaceful domestic use, storage and transport. It also provides for expanded cooperation between and among States regarding rapid measures to locate and recover stolen or smuggled nuclear material, mitigate any radiological consequences of sabotage, and prevent and combat related offences. The Amendment constitutes an important milestone in the global efforts to combat nuclear terrorism.