Today, we will discuss project assumptions and constraints by looking at a real-world example.

Imagine you want to go shopping at a mall that takes one hour to reach by car.

You assumed that you would leave your home at around 6:00 pm and reach the mall by 7:00 pm.

This is an example of an assumption, something you believe to be true. 

What about constraints?

In the shopping example, you can think of two. The first constraint is money. If you have 500 USD in your hand, that’s all you can spend on this shopping trip. The second constraint is the mall’s closing time; let us say it is at 10:30 pm. This means you cannot continue your shopping after that.

Similarly, projects also have assumptions and constraints. You must understand and manage these factors if you want to complete your project successfully.

Let’s dive in.

Project Assumptions and Project Constraints

Project assumptions and constraints are identified at the beginning of the project. Throughout the project life cycle, they will be refined and re-analyzed. Project assumptions and constraints are key to many processes in the PMBOK Guide.

An essential aspect of your project, assumptions, and constraints are not managed like requirements or risks. However, documenting them helps to protect you from future aggravation. You should outline your project’s assumptions and constraints in the project scope statement.

Project Assumptions

An assumption is what you believe to be true. These are anticipated events or circumstances that are expected during your project’s life cycle. You make assumptions based on your experience or the information available on hand.

Assumptions may not end up being true. In fact, they can sometimes be false and may negatively affect your project, adding risk to the project.

For example, let us reconsider the earlier example. You assumed it would take one hour for you to reach the destination. What will happen if you are stuck in traffic and can’t reach the mall on time?

Your assumption turned out to be false. Now your shopping is at risk because you don’t have as much time as planned.

This can also happen to your project.

For example, you assumed that you could get the necessary equipment whenever you needed it. However, you couldn’t get it when the time came due to shortages or supply-chain problems.

Now you are in a difficult situation.

Assumptions play an essential role in developing a risk management plan. Therefore, as a project manager, you must analyze each assumption and predict its impact.

Project Assumptions Examples

  • You will get all the resources you need.
  • During the rainy season, cheap labor will be available.
  • All relevant stakeholders will come to the next meeting.
  • Your team members have all the required skills.
  • All equipment is in good condition.
  • The supplier will deliver consumables on time.

You can see how, if any of the assumptions above turn out differently, your project will be radically affected.

Project Constraints

Project constraints are limitations imposed on the project, like the budget, schedule, or resources.

The PMBOK Guide recognizes six project constraints: scope, quality, schedule, budget, resources, and risk. Out of these six, scope, schedule, and budget are known as the triple constraints.

These constraints are defined at the beginning of your project, and you must work within their boundaries.

A constraint can be of two types:

  1. Business Constraints
  2. Technical Constraints

Business Constraints

Business constraints depend on the state of your organization. They are high-level constraints and often defined when the project starts, like time, budget, and resources.

Changes to these constraints are rare, and the project management team has to work within them.

Technical Constraints

Technical constraints limit your design choices. They are fixed, and any change to the technical specifications can affect your project planning.

For example, let’s say you’re constructing a pipeline. According to the design, the pipeline should withstand a certain amount of pressure; this is your technical constraint, a fixed reality.

Every project has constraints. Therefore, you must identify all of them and develop your plan accordingly. Constraints are outside of your control, imposed by clients, organizations, or government regulations.

Project Constraints Example

A few examples of constraints are:

  • You must achieve the first milestone within one month.
  • You have to work with the available resources.
  • You will only have two site engineers.

Assumptions Vs Constraints

The following are a few differences between assumptions and constraints:

  • Assumptions are believed to be true, while constraints are true in nature.
  • Assumptions are good for the project, while most of the time, constraints are not favorable to the project objective.
  • If assumptions become false, it is bad news for the project. However, if constraints are false, it is positive.

Assumptions and constraints play a vital role in the planning process as the foundation of your project management plan. 

Any assumption is a potential risk for your project, because, if any assumption is incorrect, you are in trouble. Your risk management plan heavily depends on assumptions and constraints. Failing to identify any of them can affect your project. 


Assumptions and constraints are an important part of your project. They need to be identified, controlled, and monitored continuously. 

An assumption is a condition you think to be true, and a constraint is a fixed limitation on your project. Assumptions need to be realistically analyzed, while constraints need to be clearly identified throughout the project lifecycle. Managing assumptions and constraints are necessary to complete your project with minimal obstruction. 

Project assumptions and project constraints are essential topics from a PMP certification exam point of view. You may see questions about this.

What about assumptions and constraints on your project? Please share your experience through the comments section.