Book excerpt: Public Opinion and 20th-Century Diplomacy explores both the influence of public opinion on diplomatic decision making in international history, and its emergence as a legitimate field of study for international historians. The book uses five case studies to examine the impact of public opinion on the "high" politics of diplomacy. Incorporating a variety of methodological approaches, the book looks at: -British policy at the Paris Peace Conference -French policy in the era of 1930s appeasement -Policy choices of the US during the Vietnam War -Global responses to apartheid-era South Africa -Public attitudes across the EU regarding European integration This book demonstrates the vibrancy of public opinion research to date and the possibilities for future lines of study.