Envy - Freeness and Implementation in Large Economies ∗ Matthew

We show that an asymptotic envy-freeness condition is necessary for a form of robust approximate implementation in large economies. In settings where agents’ allocations can be made excludably, asymptotic envy-freeness is also sufficient for implementation, while in nonexcludable settings it is not sufficient. ∗We are grateful for financial support from the National Science Foundation under grant SES-9986190. We thank Andy Postlewaite for helpful comments on an earlier draft. †Division of Humanities and Social Sciences 228-77, California Institute of Technology, Pasadena, California 91125, USA. Email: [email protected] ‡Graduate School of Business, Stanford University, Stanford CA 94305, USA. Email: [email protected]