Mastering The Triple Constraint

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In chaos theory, the Butterfly Effect shows how even the slightest change in an initial set of conditions can have a dramatic impact on future events or conditions. Similarly, in project management, the Triple Constraint refers to the three critical and interrelated factors in any project; Scope, Cost, and Schedule, and how even a small change in one of the factors impacts one or both of the other factors.  triple-constraintBy understanding of the dependency between scope, cost, and schedule, coupled with good upfront planning, you are sure to see an increase in your project success rates!

On any project, you’ll need to keep in mind that your project plan is not static and that change is the only constant.  The goal is not to prevent any changes to the project plan, it is to actively anticipate the variables and manage them as they present themselves.

A good project manager has already identified the risks to scope, cost, and schedule, estimated likelihood of each risk, and identified options ‘just in case.’ To illustrate the dependency between Scope, Cost, and Schedule, let’s look a few familiar scenarios:

  • Scope changes –  it is no surprise that Scope Creep is often cited as the #1 project threat! As various stakeholders want to add more bells and whistles (requirements) you need to understand how to adjust cost (resources) and the schedule accordingly.  When your boss or client says that they want to add some more features to the project, your response, with a smile, is ‘Of course!’ and then you sit with them and review how the expanded scope will in turn affect the cost and/or schedule
  • Cost changes – Sometimes, your project is presented with a change in cost/resources.  How many of us have experienced losing key staff who have either quit or been diverted to another project?  The loss will most likely affect either your project schedule or the project scope.  A good project manager will already have planned for this common risk and will be ready to propose some schedule or scope options to accommodate the resource reduction
  • Schedule changes –  Your boss may call you on Thursday and say that she needs your report on Monday, which is one week early.  Your options, after you stop grumbling to yourself, are to increase resources (by working over the week-end or enlisting a co-worker to help you on Friday) or reduce the scope or quality of the report (which carries some risks).

So, on your next projects, consider the Triple Constraint and commit to some upfront risk planning.  You’ll be better able to anticipate change, manage your options and, in turn, increase your project success rates.

Donna Catalano, owner of Eastlake Solutions, helps nonprofit organizations assess and strengthen their internal capacity and position themselves for future growth.  Services include consulting, speaking, training, facilitation, and publications in the areas of capacity building, project management, change management, strategic planning, and organizational development. Eastlake Solutions is based in Chicago and Denver –

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