Some see the twentieth century as roughly divided in the middle. They see the first half as an era of imperialism, economic fluctuation and collapse, and massive global violence; the second half as a period of less trauma. Although the latter has been replete with searing regional wars and harsh rivalry between the cold war's Western and Eastern blocs, broad-scale peace has been preserved. Vast nations have become independent, and, despite gross, sometimes worsening, inequalities, average real incomes, health, life spans, and levels of schooling have risen in much of the world, including many of the poor countries of Latin America. Asia, and Arica, collectively referred to as 'the third world, ' during the decades of East West rivalry. It is in this world that governments have tried to engineer development. Those intervening have included not only governments of the areas themselves but also external states acting through their own bilateral agencies and various multilateral institutions that governments have jointly sponsored and partly owned. The formation of such multilaterals surged after Second World War, and many of those created, whether or not beleaguered, have endured. The present work is about one of the postwar multilaterals that started quietly but that by the 1990s (whatever its future) had become one of the strongest of the group: the International Bank for Reconstruction and Development (IBRD), commonly known as the World Bank. To facilitate the telling of the Bank's story, it is useful to identify the defining characteristics that will resonate during the Bank's first half century, shaping the experience throughout and in some instances changing it considerably.