This is the first full-scale study of the career of late-eighteenth century entrepreneur William Duer. A member of the New York State Convention and the Continental Congress, and Assistant to the Secretary of the Treasury when the Federal government was organized, Duer had a role in all the significant changes that occurred during the revolutionary period. In addition, Duer was a stock speculator, a land promoter, an army contractor, and merchant. While he was Secretary to the Board of Treasury, Duer floated the Scioto Land Comapny, one of the biggest speculations ever attempted in the United States.