The development of a national market was one of the key features of the nineteenth-century economy. In this process, innumerable institutions played a role, some large and well-known, others neither so large, nor quite so well-known, at least to the public at large. One such organization was the New York Cotton Exchange. It evolved in the aftermath of the Civil War, and over the years grew from an informal, even ad hoc organization into a formalized institution that served both public and private functions. This article by Mr. Lipartito explores the development of the Exchange and its place in the shifting national market for cotton.