This chapter, devoted to the events of 1929–30, opens three chapters – Chapters 3–5 – which analyse collectively the Morgan role in the coming and development of the Depression between 1929 and 1933. Chapter 3 has as its centrepiece the Morgan effort to end what the partners saw as postwar economic warfare that was undermining European and, by extension, American prosperity. The concrete form that this took was the Young Plan (1929) that revised reparation as well as the establishment of the Bank for International Settlements, conceived as a forum to allow central banks to overcome pressing international questions. The Wall Street Crash, which surprised the Morgan partners – they did not see it coming – was, in the Morgan view, ephemeral. This stance helps us understand why Wall Street was slow to appreciate the downturn. The chapter argues that there was division among the Morgan partners as 1930 progressed on the state of the American and global economy. Leffingwell, the partnership economist, was pessimistic by the summer of 1930. In contrast Lamont continued to evince an optimistic outlook, driven in part by his desire to remain in step with the Hoover administration.