The Kyoto protocol has focussed attention on the identification and implementation of strategies and tactical measures to reduce greenhouse gas (GHG) emissions. Therefore, urban transportation systems planners have to find an innovative way to meet this new requirement. This paper consists of four parts. Part one is a hrief introduction to the concept of environmentally sustainable urhan transportation, fuel consumption, qreenhouse gas (GHG) emissions, and the requirements of the Kyoto Protocol, Part two describes the methodological requirements for the estimation of GHG emissions and points out the deficiencies in the existing practice. Part three descrihes how to use EMME/2 as a platform to estimate GHG emissions. Finally, in part four, conclusions are presented,