Waste prevention programmes require a range of skills to be successfully implemented. Among these is an ability to correctly assess the environmental impact of existing and future technologies and products. Waste prevention often approaches the issue of technology choice from the standpoint of resolving an existing problem. This may be effective in relieving the immediate situation, but is vulnerable to the creation of new problems that did not exist before. An ad-hoc approach to the selection of alternative technologies can lead to less than optimal results, and a tendency to simply transfer the environmental problem to another sector. The problem of choosing the most appropriate alternative technology is compounded by the multitude of environmental impacts to be addressed, including now also social and cultural impacts. In fact, despite the ready availability of low-waste technologies some environmental problems remain unresolved because the social factors have not been adequately resolved. One of the best known examples of these intractable problems is the use of mercury in small-scale mining, but others exist also. The widespread failure of effective technology transfer to developing countries often has its origin in this neglect of social factors, and cleaner technology programmes on their own are thus only partially successful.