The Military Balance has been published annually since 1959. The 2023 edition provides an open-source assessment of the armed forces and equipment inventories of 173 countries, with accompanying defence economics data. Alongside detailed country data, The Military Balance assesses important military issues, region-by-region, and includes graphics to illustrate these as well as noteworthy equipment developments. Maps this year include a focus on Russia's full-scale invasion of Ukraine and select China-Russia military cooperation activities. The book draws on the range of data carried in the Military Balance+ online database, particularly the procurement features in each regional section. The accompanying wallchart explores the military use of outer space, an increasingly important element of defence capabilities, focusing on China, Russia and the United States. For those involved in defence and security policymaking, analysis and research, The Military Balance is an indispensable source.