SAFEPATH – Using problem solving techniques to model the complex highways system

The CEDR SAFEPATH project is tasked with gathering evidence on how to safely increase highway capacity, without physically building more roadspace. SAFEPATH used a systems analysis approach to examine the problem, which involved the development of models known as means-ends, objective tree, and causal relations.

The result is a systems diagram for highway capacity and road safety to link different ways (means) for increasing highway capacity to measurable criteria. This supports informed decisions and provides the foundation of a good practice guide.


Scott Stephenson, Principal Research Scientist, AECOM

Scott works on operational research for transportation clients on subjects such as road user behaviour and compliance, road and rail safety, and highway capacity.

He uses research tools such as driver simulation, proving ground tests, and on-road trials. He holds a PhD in Engineering Surveying and Space Geodesy, with a background in surveying and mapping before joining AECOM in 2014.