The Essay on the Nature of Trade in General was written in the early 1730s by Richard Cantillon, a speculator and banker who had made a vast fortune during the Mississippi and South Sea Bubbles of 1719-20. The work remained unpublished for about two decades, but when it appeared posthumously in Paris in 1755 the book was immediately recognised as a brilliant genre-defining contribution to the then emerging intellectual discipline of political economy. A degree of mystery has always surrounded the publication of the Essay. Cantillon died under mysterious circumstances in 1734, but the work survived in various manuscript forms. This edition offers an innovative mode of presentation, displaying for the very first time all print and manuscript versions of the Essay in parallel. This allows the reader to appreciate different formulations of Cantillon’s seminal contributions to a range of topics, including his circular flow analysis, monetary theory, theories of value and distribution, the role of the entrepreneur, spatial economics and international trade. Richly annotated and accompanied by a detailed study of the historical background of Cantillon’s writings, this new scholarly edition offers many new insights into this early masterpiece of economic theory.