The SIPRI Yearbook is an authoritative and independent source of data and analysis on armaments, disarmament and international security. It provides an overview of developments in international security, military expenditure, weapons and technology, arms production and the arms trade, armed conflict and conflict management, and efforts to control conventional, nuclear, chemical and biological weapons.This 53rd edition of the SIPRI Yearbook covers developments during 2021, including:US BLArmed conflict and conflict management, with an overview of armed conflict and peace processes across the Americas, Asia and Oceania, Europe, the Middle East and North Africa, and sub-Saharan Africa, as well as a focus on global and regional trends in peace operationsBE UE US BLMilitary expenditure, international arms transfers and developments in arms productionBE UE US BLWorld nuclear forces, with an overview of each of the nine nuclear-armed states and their nuclear modernization programmesBE UE US B