When your project sponsor says, “That all sounds fine, but can you deliver it by the end of the year?” they are telling you what constraints apply to this project. The output has to be complete by the end of the year – or at least, they would like it to be!
Delivering on time is regularly a challenge for project managers, but when you know that the project sponsor values an on-time delivery, you can at least do something about it. Scheduling accurately in P6 for example, or making sure you have enough resources and budget to deliver what is required by the date.
This is an example of a project constraint. We come across them often, but perhaps don’t always recognize them as constraints. Whether you are working in the PMO and need to be able to specify corporate constraints to project managers, or you are acting in the project management role and need to define what success looks like for your stakeholders, this article will help! We outline the most common project management constraints and answer some common questions, so you can better manage your projects and stakeholder expectations.
What is the Project Management Triple Constraint?
Let’s define constraints in project management.
A constraint is something that imposes boundaries on your project activity. It puts limits on what you can do or how you do it. The triple constraints of project management are time, cost and scope.
Time is a project constraint because often projects have fixed deadlines or milestones that must be achieved at a certain time. For example, a new product has to be ready before the Black Friday sales period.
Cost is a project constraint because companies naturally have to limit the amount of money they spend on any activity. It would not make business sense to give project managers an unlimited budget to achieve their work. Costs are normally specified in the business case so the constraint (i.e. how much you can spend to get the job done) is documented there.
Scope is a project constraint because the work to complete the project is defined and has a defined end goal. For example, the new product must include functionality to allow schoolchildren in remote classrooms in rural areas to access their homework assignments every day. If the project completed and this core element had not been delivered, the project would not be seen as a success. Project managers put boundaries around the scope of the work, otherwise they would be making changes and tweaking the end result forever! The work would never get finished.
Constraints are trade offs. If you switch up one thing, it will have an impact on something else. You have to constantly balance the different elements to ensure you get an acceptable result for your project stakeholders.
What is the Project Management Triangle?
The project management triangle is the project management triple constraint in diagram form. Each side of the triangle represents one of the triple constraints: time, cost or scope. Quality is represented in the middle, as the central theme. Any changes to the elements on the outside of the triangle will affect the quality of the end result, so you need to be mindful of that.
The project management triple constraint triangle model has been around for a long time and it’s commonly referred to in project management training. However, today, project management and PMO thinking has moved on from these three elements. There’s a strong argument for saying there are more constraints than three. Let’s look at some broader examples of project constraints.
What is an Example of a Constraint?
Looking at real examples of project constraints (like in this article) can help you understand how the triangle model is going to affect your project.
Here are some other examples of constraints. You can use these in your business case and planning to see how they will affect your project.
- Project design or architecture: You may have to use specific design approaches to deliver your solution.
- Third party commitments: You may have to meet requirements around certain third party arrangements from contracts.
- Regulation: The law tends to be a significant constraint! You have to ensure your project delivers a solution that is compliant with regulation.
- Staffing: You may not have access to the exact resources you need, so staffing could be a constraint for your project team.
- Facilities: You may have to use certain facilities, like the company data center, or you may not have access to certain facilities.
- Physical: You may have to limit or scale your deliverables to fit within the available physical space e.g. components within electrical goods.
- Risk: Companies have a risk tolerance and you may not be able to exceed that on your project. This may determine what kinds of steps you can take or solutions you can use, to ensure you stay within the corporate risk appetite.
- Technology: Particular IT solutions might be mandated by company policies and you may be restricted to only using those.
These won’t all be relevant to your project, but you can see from this list of constraint examples that some of them might be. This is not an exhaustive list, so use it as the basis for your own project management documentation and discussion. The organization’s PMO may also have a list of common constraints that appear in business case templates, for example, so you can also draw inspiration from those.
Why is the Project Management Triple Constraint Important?
Regardless of how many constraints you believe there are on projects – and on your project in particular – we still tend to refer to the ‘triple’ constraint as a catch all to start a discussion about the boundaries for projects.
The greatest constraint for a project is usually one of the triple constraints. However, it could be something else entirely, like customer satisfaction or ability to satisfy a regulatory body. The best way to determine the most important project constraint is to talk to the project sponsor. Ask what they consider to be the boundaries for this project. What are the most important elements to deliver to? Perhaps they can give you some flexibility on budget as long as you hit the final date. Perhaps there is some wiggle room for the project schedule as long as you don’t spend more than a specific amount. They’ll know what constraints they are setting for the project but this might be sub-conscious, so you’ll have to ask questions to get the heart of what they are expecting.
Having scope as a constraint helps limit what the project will deliver. This is helpful for managing change requests and scope management. When you know what the original scope was (and that was agreed) you can adequately manage requests for changes. You can assess what impact a change will have and then make an informed decision about whether you want to go ahead with the change or not.
The project management triple constraint idea that has evolved over time but is still relevant today. Ultimately, project managers need to consider how to uncover the constraints relevant to their project. And then how to manage the project successful taking the project management triple constraint into consideration. Once you’ve worked that out, you are well on the way to delivering projects that routinely meet their stakeholders’ approval.