The UK’s departure from the European Union has given it a once-in-a-generation opportunity to re-examine its place in the world and develop a new strategic posture. As the rise of China and the movement of economic growth shifts to the Indo-Pacific region, British thinkers have begun to think about Global Britain through an Indo-Pacific lens. Naturally, the threat to the rules-based order and free and open shipping lanes presented by China’s activities in the South China Sea and growing naval power have meant that British policymakers have had to consider the hard power components of its posture and involvement in regional security groups like the Quadrilateral Security Dialogue. This chapter looks at whether Britain could or should be a Quad member and examines the arguments and assumptions underlying the debate.