The aviation sector generates specific emissions having an impact on climate change. The Intergovernmental Panel on Climate Change special report on aviation (1999) has revealed the importance of those impacts on global warming. Its total climate impact is by far more important than only its CO2 emission climate impact. In addition to CO2, also condensation trails, NOx emissions and cirrus cloud formation have a significant impact on climate change. Despite these statements, yet, emissions from international air are not targeted by the Kyoto Protocol commitments. Different policy measures may thus be considered for the inclusion and integration of international air transport into climate policy. The analysis of such possible measures is of particular interest for Belgium, given the importance of this sector in its economy and territory. Belgium has also considerable number of overflights due to his location in the so-called FLAP zone (Frankfurt-London-Amsterdam-Paris). There are several ranges of measures to reduce the impact of aviation emissions, including changes in aircraft and engine technology, fuel, operational practices, and regulatory and economic measures (IPCC , 1999). Research on global environmental change increasingly takes place in interdisciplinary teams, in which scientists in different fields have regular discussions and dialogues, and think together in an interdisciplinary way (Welpa et al., 2006). On the basis of these considerations the Aviation and the Belgian Climate Policy Impact (ABCI) Project was charged to provide an in-depth analysis and assessment, from a technical, environmental and an economic point of view. In the attempt to integrate the findings on aviation and Belgian climate policy with other issues of concern - such as the other environmental impacts related to air transport it was decided to use a Multicriteria analysis. The intention of this paper is principally to show the Multicriteria analysis methodology with the software application related to a complex decision problem on behalf of sustainable transport policy support.