During the recovery from COVID-19, inflation in the United States and many other countries surged to its highest level in more than 40 years, inflicting enormous pain on households and businesses, upending fundamental patterns of economic activity, and changing the course of politics and societies worldwide. To distill lessons from that era, the Peterson Institute for International Economics spearheaded a special project―codirected by Karen Dynan and David Wilcox―convening leading experts to examine different facets of the inflation surge, including supply-side disruptions, demand dynamics, labor markets, fiscal and monetary policy interactions, and inflation measurement. Their published papers are brought together in this PIIE Briefing.