ScenPlanImage2 This quote from a recent guidebook on scenario planning highlights one of my major problems with scenario planning.  Despite attempts to standardize it, the field not only lacks a central methodological basis, it also lacks a common language and even a consistent terminology.  I find this problem most acute when people talk about what scenarios are.  The answers can range from, “what will likely happen in the future?” to “what could happen in the future?” to “what do we want to happen in the future?”  Sometimes, scenarios only deal with “how will we adapt to the future?”  We don’t have a consistent terminology or typology to describe these different ways of looking at what scenarios are and these different approaches to scenarios planning.

With the passage of MAP-21, the Federal Highway Administration (FHWA) has given even more impetus to scenario planning as used in transportation planning, thus giving new life to the practice.  A spate of recent studies in scenario planning, however, has failed to address a fundamental issue having to do with the overall framework or “typology” of scenario planning.  Even the standard FHWA guidebook on scenario planning doesn’t really address this broader issue of framework.  Under “Types of Scenarios,” the Guidebook says simply, “There are many types of scenarios.  Some scenarios focus on telling a story about the future as a way of visioning possible changes.  Others do not involve narratives but rather sets of assumptions that examine future possibilities.”  While not inaccurate, this is hardly a definitive typology of scenario planning.

What Others Have Attempted

A few researchers have tackled the task of developing a typology of scenario planning but little consensus on such a typology exists.  In 2002, Ged Davis, working for Shell Oil developed a fourfold typology based on key questions one could ask of the scenario planning process.

Chart1A later attempt to develop a typology of scenario planning by the Royal Institute of Technology in Stockholm was also based on a series of questions that can be asked about the future:

chart2Most recently, FHWA, in its guidance for MAP-21, has loosely defined a typology of scenario planning through a discussion of the ways in which scenarios might be used in the transportation planning process:

Chart3All of these are useful ways of looking at types of scenarios.  However, they are hardly consistent and this professional confusion about the broader framework of scenario planning highlights a need to unify our terminology, to develop a common language for a basic typology of scenario planning.

Towards a New Typology

In this brief blog post, I would like to suggest at least one possible direction to explore in the development of such a typology.  The “cheat sheet” chart below, while relying heavily on the Royal Institute of Technology study cited above, expands this structure into a series of four key questions about the nature of a scenario planning effort.

Through this potential framework, one can first classify scenario planning based on the fundamental question of what they are seeking to know about the future – do they look at the likely future, at all possible futures, or at a desired future?  From this starting point, the scenarios can be further classified by the factors that affect that future – external ones, such as the cost of energy or demographic changes; or internal ones, such as policy direction or investment and funding actions.  Finally, for those types of “aspirational” scenario planning efforts that specifically explore responses to change, these responses can be further classified into “do nothing” responses that shows what the outcome will be if no actions are taken; and “drive change” responses that show how purposeful policies and actions may influence the future.

Chart4This last issue – how different policy responses may influence the future – can be roughly modeled as shown below.  The chart shows the relationship between policy choices and how they may influence future trends.  It shows, in red, a “likely” trend and, in green, a “desired” or aspirational trend, along with additional potential trends in blue.  Two possible policy responses to these futures are shown as dashed lines.  The dashed red line shows the probable outcome if “no change” policies are pursued.  This outcome is more or less in line with the “likely” future that was previously modeled.  However, the green dashed line shows the probable outcome if “drive change” policies are pursued, an outcome much closer to the “desired” trend that was previously modeled.

Chart5Next Steps?

If our profession is to address our self-imposed challenge, that of bringing some standardization to the scenario planning process, it will take a lot more than a “cheat sheet” for scenario planning.  The Cheat Sheet above only points to one potential exploration for a typology.  However, it will take a very robust research effort that looks both in breadth and depth at the state of the practice and state of research into scenario planning, to bring some manner of consistency to the terminology and typology of scenario planning.  This challenge is perhaps more pressing than any potential technological or methodological refinement in the field that may emerge in the coming years.

–Vlad Gavrilovic, Cities That Work Blog