CERO was developed during doctoral research at the Royal Institute of Technology,1 and the model has been published and peer reviewed in four international scientific journals.CERO analysis is based on the “backcasting” planning perspective, which provides a basis for decision making in the organisation, addressing the following three questions, in order:

1.What targets have been set for the future as regards travel emissions, travel costs, and employee working conditions?
2.Where does the organisation stand today in relation to these targets?
3.What target-oriented policies should the organisation prioritise in order to move from the present situation to the targets?