A practical application of sustainable development (SD) is unfeasible without being guided by a logical framework and suitable mechanism. Popular conceptions of SD are various, and non-rigorous, so that they do not offer a viable point of departure for any practical programme, that Engineers could follow. There is an urgent need to return to the basis provided by the form of words of the Our Common Future (OCF) definition of SD to rediscover the true meaning of the concept. In OCF the context for the SD definition is set. The key ideas of environment and development are refocused giving these words a specific meaning framing the Brundtland definition which consequently should never be quoted out of context. SD is a non-negotiable unambiguous principle, a restatement of the ‘Hicksian’ principle of income that is the foundation of sound and wise household management. This paper proposes a mechanism for practical SD that allows the ordering of the popular vocabulary of the subject and leads to useful insights into the nature of SD itself not just for Engineers but for sustainability practitioners in all walks of life.