Pii: S0305-750x(00)00072-3

Ð In developing countries, urban clusters of informal ®rms such as brick kilns and leather tanneries can create severe pollution problems. These ®rms are, however, quite dicult to regulate for a variety of technical and political reasons. Drawing on the literature, this paper ®rst develops a list of feasible environmental management policies. It then examines how these policies have fared in four independent e€orts to control emissions from informal brick kilns in northern Mexico. The case studies suggest that: (a) conventional command and control process standards are generally only enforceable when buttressed by peer monitoring, (b) surprisingly, clean technologies can be successfully di€used even when they raise variable costs, in part because early adopters have an economic incentive to promote further adoption, (c) boycotts of ``dirty'' goods sold in informal markets are unenforceable, (d) well organized informal ®rms can block implementation of costly abatement strategies such as relocation and (e) private sector-led initiatives may be best suited for informal sector pollution control. Ó 2000 Elsevier Science Ltd. All rights reserved.