The fundamental role of Great Britain's economy in the international economic system in the century preceding the First World War is demonstrated by a number of variables, which have drawn the interest of many scholars. The focus here is on capital flows. The main difficulty encountered in this work arose from a shortage of documentation on economic data in the historical period under consideration, which has been tentatively reconstructed, on the basis of a number of estimates, subjected to a close comparative scrutiny. The book provides a valid guide to anyone wishing to improve their understanding of the so-called "pax britannica" which, at that time, rested on the canons of free trade and the gold standard. This historical period is considered by many to be the first experience of capitalist globalization. In this sense the book is also intended to provide useful reading for those who want to reflect on the possible future evolution of the world economy.