Luigi Einaudi (1874-1961) was a leading liberal Italian economist, economic historian and political figure: Governor of the Bank of Italy, Minister for the Budget and President of the Italian Republic. He was a prolific writer in all fields and his writings testify to his outstanding contribution to economics during his long career. He is best know for his work on public finance and the study of the principles of taxation, although he also focused on money and banking. Throughout his career Einaudi argued the economic and political case for European unity, anticipating the need for a common market and monetary union. His writings on political and economic liberalism are enlivened by a down-to-earth conception of the market and grounded in extensive historical and institutional knowledge. This is the third book in a three volume collection of Einaudi's works, which have been made available in English for the first time.