19 May 2008
The Triple Constraint
In interviewing potential Project Management candidates for our clients’ initiatives as well as our own, there are a number of key touchstone questions that we use to assess the experience and capability of potential new hires. Generally speaking the one question that can lead to an organic set of follow up questions that provide a lot of insight regarding the suitability of a particular candidate is the triple constraint question.
Now, traditionally some candidates are stumped by this question until we ask them the question a different way – that is, “can you discuss for us the philosophy behind the project management triangle?” The fundamental concept is this: a project’s main adjustable dimension are: schedule, cost, and scope (we tend to think about scope as a function of features and quality). The basic point is that one can be given the option to control any two of these dimensions, but the third dimension must be adjustable. From this starting point an interviewer can establish an incredibly rich set of questions and follow-ups in order to ascertain the experience, analytical acumen, and negotiation skills of a potential candidate.
Generally speaking, this philosophy is a sound an important academic principle.
In practice, however, 9 times out of ten, the number one “immovable” dimension for most initiatives is “schedule” with “cost” following close behind. That being the case, this is one of the key reasons that we tend to favor the Agile approach which tends to emphasize the capability of the team (leading to the effective scope acheivable) in the context of time-bound development.
