This book presents evidence that public debts in the advanced economies have surged in recent years to levels not recorded since the end of World War II, surpassing the heights reached during the First World War and the Great Depression. At the same time, private debt levels, particularly those of financial institutions and households, are in uncharted territory and are (in varying degrees) a contingent liability of the public sector in many countries. Historically, high leverage episodes have been associated with slower economic growth and a higher incidence of default or, more generally,...