Since it is able to secure important services, to minimize environmental and health risks and to promote innovation, workplaces and economic growth the substitution of environmentally hazardous substances by safer alternatives holds great potential for a sustainable development of the chemical industry. Therefore the aim of a legal promotion of substitution has recently entered the chemical legislation such as the REACh Regulation. Because of the potential but especially the complexity of such a legal promotion the author analyses existing approaches within the chemical, pesticide and biocide regulations in terms of their effectiveness and their proportionality.