A while back I wrote about a characterization framework for projects, in which I differentiate projects based upon the level of uncertainty involved, and the potential consequences of that uncertainty. I’m hardly the first person to try and differentiate projects in some systematic way – I highlighted a few other efforts here.
In this post, I look at how some of the major project management methodologies fit on this framework. I use “project management” here in a much broader sense than conventional usage: any method for organizing and undertaking project tasks carries implications ofr how that process can or should be managed, so even methods which are normally thought of as being about execution rather than managing, are in a wider sense PM methods.
In a plan-driven methodology such as those advocated by PMI IPMA etc, project goals are identified and the necessary steps to achieve this goal determined. The steps are organized into an optimal sequence given resource and other constraints to form a project plan. This plan is then followed, with the objective of management being to administer the activities and to deal with deviations from the plan.
Considering this methodology on our framework, its effectiveness can be seen in the ideal case to be independent of the consequences axis. As the objective of planning is to anticipate and avoid surprises, their consequences are irrelevant. However the effectiveness of the plan driven methodology will vary along the uncertainty axis. The plan is inevitably based upon assumptions about the goal, methods, required effort and resource constraints among other things. As uncertainty increases these assumptions will be less valid. This can be compensated for to some extent by increased planning effort, however in the limiting case developing the plan itself becomes a dominant project task. The upshot is that as uncertainty increases, deviations from plan will increase, and the project will become less plan driven, and more driven by ad-hoc responses to surprises.
The plan-driven methodology is an example of an uncertainty-limited methodology, as shown in Figure 2.

Another such example is that of the problem structuring methodology. Problem structuring methods such as the Soft Systems Method (SSM) focus upon the definition of the objectives and environment of the project. Their effectiveness is again independent of the consequences axis, as implementation – and therefore the opportunity for consequences to occur – is assumed to be trivial. But effectiveness again varies along the uncertainty axis. As noted above, the relative importance of implementation and validating assumptions – or problem definition – changes. At low uncertainty levels, where the situation is relatively clear, “the process of inquiry into the problematic situation” [67 p S50] becomes a trivial one, and problem structuring methods become irrelevant. The problem structuring methodology is thus also uncertainty limited, but the limit is at the lower bound.
Not all methodologies are limited by uncertainty. The simplest project methodology is the ad hoc one, also known as “winging it” or “hacking”. In this methodology, no planning or preparation is undertaken, and the project team simply follow their noses and deal with problems as they arise. This methodology’s effectiveness is in the ideal case independent of uncertainty, as the lack of anticipation means that everything comes as a surprise – uncertainty is effectively maximum in all cases. However its effectiveness is highly dependent upon consequences: lack of any control system means that any event which the team is unable to handle is likely to quickly run away to disaster, and that it will not necessarily be known whether the event has been handled satisfactorily until too late. This methodology is thus restricted to situations where the teams ability to handle unexpected events is high (meaning extremely small and expert teams), and “disasters” cannot be overly serious: the methodology can be considered to be consequence limited.
A similar argument can be applied to the Agile methodology. This is similar to the ad hoc methodology in that uncertainty is dealt with by adaptation rather than anticipation. The technique is again limited in the consequence dimension by the team’s ability to cope with the unexpected (which is dictated by factors such team size, distribution, empowerment and competence), and by the magnitude of the worst case disaster. However techniques within the Agile methodology are largely aimed at providing control systems to mitigate these limitations, by maximizing team responsiveness and providing rapid feedback as to the effectiveness of responses. The upper consequence limit under which Agile techniques are effective is thus higher than for the ad hoc method, again as shown in Figure 2.
The limiting values shown in Figure 2 are arbitrary, and in fact a tapering off of effectiveness rather than a hard limit would be more realistic. However the graph shows clearly the respective “comfort zones” of the methodologies discussed, and areas of overlap and of lack of coverage.
In areas of overlap, the issue for methodology selection is not so much one of effectiveness as efficiency. For example in the area of relatively low consequences and uncertainty, both Agile and plan driven methodologies are effective. However the cost drivers of each are different. Plan driven methods impose significant overhead costs in documentation and control, although these an be minimized by “lightweight” implementations (see for example [68]). On the other hand, as a “learning” approach Agile has a lower ideal efficiency than the “prescriptive” approach [69, 70], imposing risks of wasted work and suboptimal sequencing. Which cost dominates will depend on the particular circumstances of the project in question.
Although projects with significant uncertainty and high consequences have been managed successfully, the graph shows a gap in this area between the methodologies considered. The high incidence of failure in large capital projects, particularly in the IT and construction fields [71-74] suggests that this is a combination which is not easily manageable using existing project design methodologies.