A geometric device showing allocations of 2 goods to 2 consumers in a rectangle with dimensions equal to the quantities of the goods. Preferences enter as indifference curves relative to opposite corners of the box, tangencies defining efficient allocations and the contract curve. First drawn by Pareto (1906), based originally, though only partially, on a diagram of Edgeworth (1881). This and the Edgeworth production box are often called just the Edgeworth Box, even though Edgeworth never drew either.