By its very nature, investment in r&d is a challenging proposition. It is a decision made today for an uncertain return in the future. Moreover, it has become more complex with the introduction of sustainable development considerations into the decision-making process. In this paper, the effect of environmental policy on the economic framework within which new technologies must compete is discussed, and analytical techniques which help assess these complexities are described. The return on an r&d investment is determined by the competitiveness of the resultant innovation at the time of its eventual application. A new technology is competitive relative to a given economic framework (which includes such factors as alternative technologies, availability of investment capital, trained human resources, etc).government involvement in establishing goals and timetables for environmental protection signficantly affects the evolution of the economic framework in which new technologies must perform. To be successful in the ‘sustainable development’ age, the r&d investor must be able to anticipate the effect and development of government environmental and economic policy. Mathematical modelling is a valuable tool to help the investor and policy-maker appreciate the key risk factors and to understand the effect of environmental and economic policy on desired outcomes. For r&d, most model development has focused on policy development and is not very useful supporting the business decisions msociated with effective r&d investment. In this paper, the interaction bebeen government policy and business decision-making is discussed, and a methodology, supported by a model, is presented to aid r&d investors to take environmental and sustainabilip issues into account when assessing the future competitiveness of technology.