Mun was one of the merchants consulted by the government about the causes of the depression and was a member of the great commission of trade set up in 1622 to make recommendations concerning economic policy. On the commission, he opposed successfully the advocates of two different policies, each based on a distinct theoretical analysis of the mechanism of foreign trade. One group of advocates held that the export of silver was caused by the undervaluation of silver coin in England and urged therefore that sterling be devalued: this view found articulate expression in Edward Misselden’s Free Trade (1622). A second group believed that excessive export was intrinsic in foreign exchanges and advocated exchange control with a fixed exchange rate: this view was, in turn, forcibly presented by Gerard de Malynes in The Maintenance of Free Trade (1622) and elsewhere. Mun composed, or helped to compose, a series of papers directed against both these views, and these papers formed the substance of a book which he completed between 1626 and 1628 and which his son published in 1664: England’s Treasure by Forraign Trade.