Abstract: We evaluate the performance of an environmental market in a less developed country on the basis of the experiences of the particulate matter control program of Santiago, Chile. We find that grandfathering the permits has created economic incentives for incumbent sources to more readily declare their (historic) emissions in order to claim any permits. In addition, the market has not fully developed because of transaction costs, regulatory uncertainty, and incomplete enforcement. Nonetheless, it has provided sources with the flexibility to adapt to new market conditions. Our analysis of this particular experience indicates that market-based policies can provide important advantages over traditional command-and-control policies even under limited institutional capabilities. Copyright 2002 by the University of Chicago.