The results of compliance demonstration test programs for new wide-bodied aircraft powered by high-bypass-ratio engines showed that in some cases the aircraft noise levels were well below those of the requirements. This prompted a number of investigations, both in the US and internationally, to determine the feasibility of modifying the noise certification standards to be more stringent for future aircraft types. These investigations led to the conclusions that modifications were in order, but there has been no general agreement on the specifics of those modifications. It is essential that new noise certification requirements be established to ensure utilization of the best noise reduction features available to a designer to minimize noise disturbance in communities around airports. However, it is just as important that the noise requirements permit orderly development of an efficient air transportation system. These two requirements tend to be in conflict. It is therefore necessary that the noise certification requirements be based on sound technical principles and that all implications of the requirements be thoroughly understood before their adoption. The purpose herein is to suggest an approach which can satisfy the conflicting needs of minimum community noise disturbance and development of an efficient air transportation system.