In Project Management the triple constraint can be defined as the relationship between the three factors of time, cost, and scope. Ideally these three constraints remain neutral throughout the lifecycle of a project. Unfortunately in the real world, this is rarely the case. Knowing how to effectively manage the triple constraint is critical to success of any project.
In order to understand why managing the triple constraint is so critical, let’s first examine the relationship between these three factors. Imagine a triangle with the three factors of time, cost, and scope each at separate corners. Each of these three areas represent equal, but opposing forces of a project. Typically the larger the scope of a project, the greater the cost and time needed. Sometimes, a given scope of work is required to be accomplished quickly due to pending business needs. In order to implement within a shorter duration than would normally be the case, one would need to dedicate more cost to that initiative. Conversely, when budgets and timelines are finite, external factors may require a project to accept a lesser scope of work than was originally planned. Lastly, if scope and cost are not negotiable factors, then unforeseen events may require a project to take more time than originally forecast.
Knowing these rules, one might hypothesize that any scope of work could be accomplished given enough time and/or money, however this triple constraint does have limits. For example, no amount of money would be sufficient to build a 40-story building over a weekend. Similarly, that same 40-story building would not be able to be built for $500 no matter how much time was given. You could, however, build a doghouse over a weekend with a $500 budget. In this example the scope of work is reduced due to the time and budget available. Often in real world scenarios though, the least negotiable factor of a project is the scope. Typically business leaders identify the need to execute a project, then look to determine how much time and cost that proposed scope of work will take.
So, how do we use what we know about the triple constraint to effectively manage projects?
In order to understand which factors of the triple constraint are most important to project, a Project Manager must first understand the priorities of the project stakeholders and ultimately the priorities of the project sponsor. It may very well be that an organization may have a scope that they would like to accomplish and a set budget to dedicate to that project, but not need that project executed within a hard deadline. There could also be situations that arise within a business environment that require projects to be executed with a hard deadline and therefore will have greater appetite to accept higher cost in order to achieve these goals.In summary, it is not only important to understand what the scope, budget, and timeline are for a project, but also which of these factors are most important to the project stakeholders and project sponsor. Once you understand these priorities, you can then appropriately plan your project and build in flexibility to absorb unforeseen factors that may negatively impact the project scope, schedule, or budget.
WRITTEN BY ASH SIMPSON- PROJECT MANAGER