Book excerpt: The Asia-Pacific Regional Security Assessment 2021 provides insight into key regional strategic, geopolitical, economic, military and security topics. Among the topics explored are: US−China decoupling and its regional security implications; Japan’s security policy and China; India’s emerging grand strategy; Southeast Asia amid rising great-power rivalry; Australia’s new regional security posture; NATO’s evolving approach to China; The United Kingdom’s ‘tilt’ to the Indo-Pacific; and Emerging technologies and future conflict in the Asia-Pacific. Authors include leading regional analysts and academics Kanti Bajpai, Gordon Flake, Franz-Stefan Gady, Prashanth Parameswaran, Alessio Patalano, Samir Puri, Sarah Raine, Tan See Seng, Drew Thompson, Ashley Townshend, Joanne Wallis and Robert Ward.