Triple Constraints – Friend or Foe?

By Denise DeCarlo, PMP

Many people have heard of the triple constraints, but do you really leverage them? The triple constraints are defined as Scope, Time and Resources, frequently diagrammed as a triangle with each side of the triangle containing one of the triple constraints. Scope consists of the work necessary to be performed to produce the results desired for the project. Time, of course, is the duration of time the project will consume to complete the defined scope. Resources include the money and effort expended on people (labor), services and products (for example the purchase of hardware, building materials, software, manufacturing components, etc.)

Leveraging the triple constraints by determining a distinct priority of the components, and managing the project to that prioritization can enhance the chances for project success.

Ask your project sponsor at the beginning of the project to prioritize the triple constraint components. Frequently they will say, “They are ALL important”. They are indeed all important but they should not be treated equally! Undoubtedly one of the triple constraints is more important relative to the others. For example; is the end date non-moveable due to other business commitments, regulatory considerations, or other mandatory stipulations? Or maybe the budget is fixed and your project can absolutely not exceed the approved budget level – or maybe scope is critical because you are attempting to obtain a competitive edge and your company wants to be the first in the marketplace with a given product. Find out from your sponsor which of the triple constraints is most important (and why), followed by the 2nd constraint, and then the last one.

As the project manager you will make decisions every single day based on the priorities of the triple constraint. If your sponsor has indicated to you that TIME (i.e. the end date) is the first priority, followed by resources (money) and then scope, you will do anything possible to achieve the planned end date by first reducing scope (because it’s the lowest priority of the three) and then by incurring additional resources to ultimately meet the desired end date.

This may seem “basic or obvious” but all too often we don’t have this conversation with the sponsor and the project manager either assumes a priority of the triple constraint based on their perception of the situation (which might be wrong) or worse yet – the project manager attempts to treat all three triple constraint components as being equal and fails miserably because it is literally impossible to do so. Changing one triple constraint almost always has an impact (positive or negative) on the other two triple constraints.

Now, let’s assume you did have a conversation with the sponsor at the beginning of the project two months ago and your sponsor prioritized the triple constraints as; Time, Resources, then Scope. You have submitted a significant change request (10% overall increase) to add resources to the project to ensure the project end date can be obtained (the project schedule is slipping due to critical path activities taking longer to complete than anticipated). Let’s assume your sponsor has rejected the change request saying the project can not exceed the currently allocated project budget due to recent budget cuts. You then need to discuss with your sponsor the ability to change the priority of the triple constraints. It’s apparent that Resources (money) are now the highest of the triple constraints. It’s impossible to meet the current end date with the current allocation of resources and scope. You have already reduced scope to the minimum acceptable level by the business areas (you already did this because scope was the lowest prioritized triple constraint agreed upon originally) – so your next logical option is to move out the project end date. If you sponsor says “that’s impossible” then you can remind him that you must “balance” between the three triple constraints and “SOMETHING must give”. It is essential for you to take a stand and remind your sponsor about the critical balance between the triple constraints and work with the sponsor to stabilize the project.

Conversations like this are difficult, but they are essential for the ultimate success of the project. Maybe the business areas can reduce scope some more. Is there any chance some of the budget for the project can be increased? In addition, maybe we get more internal resources and remove some of the project consultants that are more expensive. It’s time to get creative – but it’s not appropriate to compromise the concept behind the triple constraint. If you don’t push back, your sponsor will assume you can “pull it off”. It is not in the best interest of the project team (or the company) to have people work even more overtime than they already are and/or reduce the quality (i.e. testing, reviews, etc.) of the agreed upon scope (which is typically what happens).

The prioritization of the triple constraints can, and will, change throughout the life of the project. However, the prioritization should not change frequently and you definitely don’t want it going back-and-forth (i.e. Time is the #1 priority this week, Resources next week, and back to Time the following week). When the priority does change (or appears to be changing based on the behavior you’re observing from your sponsor), it should be confirmed via an overt conversation with your sponsor. This will enable you to move forward and to continue making daily decisions about your project based on the new prioritization of the triple constraints.

As the project manager, it’s YOUR job to educate your sponsor (and other key stakeholders) regarding the triple constraint concept and to manage them effectively. Anyone can UNDERSTAND the triple constraint concept; however, MANAGING the triple constraints successfully is the hard part. It’s similar to a diet – the concept of a diet is easy. If you consume less calories than you burn, you will lose weight. Easy concept – extremely difficult to implement successfully!

Another common challenge surrounding the triple constraints is the different priorities that several key stakeholders typically have. Let’s face it; our sponsor is not our only major stakeholder. We have key stakeholders from each of the business entities that are impacted by the project (internal and external to the project) and frequently the stakeholder representatives have different needs (scope) and different priorities. It’s your job as the project manager to communicate to all stakeholders the pre-determined priority of the triple constraints per the sponsor’s desire. If this priority is in conflict to what other stakeholders desire, you’ll need to manage those expectations accordingly. Ultimately, the sponsor is typically the person paying for the project, and therefore, should dictate the priority of the triple constraints.

Another area of debate surrounding the triple constraints is quality. Where does “quality” reside relative to the triple constraints? PMI® recommends having quality included in the Scope “side” of the triple constraints. This is based on the fact that quality activities such as testing, having standards and templates, quality reviews, etc. are activities that must be performed to deliver the solution to the customer based on the scope. Based on this, if you begin to get “squeezed” by your sponsor and other major stakeholders to reduce testing in an attempt to meet a deadline and not increase costs – the best recommendation you can make is to reduce SCOPE to decrease the amount of time necessary to complete testing. The less scope (features) there are, the quicker you will be able to complete testing. Testing should not be arbitrarily reduced to meet a desired end date. This reduces the quality and stability of the end solution and could permanently tarnish the successful implementation of the end product. If I am forced to reduce testing time and I’m not allowed to reduce scope – I will then request additional resources (via a change request form) to be leveraged during the post-implementation phase to support and handle the additional problems anticipated once the solution is implemented. This approach can work for IT related projects, but is not very effective for construction and engineering projects when a minimum level of quality is mandatory to adhere to safety standards.

Everything gets back to the triple constraints. You can leverage the triple constraint concept in many situations including project management conflicts and challenges. We do have options, but our options are based on leveraging the triple constraints, not compromising them! Understanding the power behind the triple constraint concept will make you a more successful and respected project manager.

PMI is a registered mark of the Project Management Institute, Inc.


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