The considerable difficulties associated with cross-border environmental management are compounded when polluters are unlicensed micro-enterprises such as auto repair shops and traditional brick kilns; such "informal sector" firms are virtually impossible to regulate in the conventional manner....

In many developing countries the informal sector, comprised of low-technology unlicensed micro-enterprises, is a major source of pollution. Environmental management in this sector is exceptionally challenging. Though clean technologies offer a means of mitigating the problem, to our knowledge...