Over the past century, the world economy has passed through a succession of phases characterized by very different levels of international capital flows. This paper asks what accounts for these dramatic shifts in the extent of capital movements across national borders. Three categories of explanation are considered. The first emphasizes the policy regime, attributing the unusual extent of capital flows prior to 1914 to the operation of the international gold standard. The second focuses on the stages-of-indebtedness sometimes thought to characterize the process of economic development. The third ascribes changes in the extent of capital flows to the boom-and-bust cycles through which international capital markets are thought to pass. Though each approach contributes something to our understanding of the phenomenon, none is totally satisfactory. I therefore suggest an alternative explanation, which lays stress on the increase in the magnitude of real interest rate and real exchange variability that has occurred over the last 100 years.
