Assumptions and Constraints in Project Management

Assumptions-ConstraintsWe always make assumptions and are bounded by constraints. These are an important part of our life whether we realize it or not. We always deal with them in our daily life.

For example, suppose you plan to go shopping at a big mall, which is far away from your home, and it will take one hour to reach there by car. You made the assumption that you will leave your home around 6:00 PM and reach there by 7:00 PM. After that you can enjoy shopping.

This was your assumption. What about the constraints?

At first glance, you can think of two constraints. The first constraint is the amount of money to be spent on shopping. If you have $500 in your hand, you cannot spend more than this amount. This is your first constraint. The second constraint can be the mall’s closing time. If the mall closes at 10:30 PM, you cannot continue your shopping after this time. You have to wrap up everything before this time.

Likewise, projects also have assumptions and constraints. It is very necessary for you to understand them if you want to complete your project successfully. A successful project manager always keeps an eye on his project’s assumptions and constraints.

The assumptions and constraints can be identified and documented throughout the project’s life cycle. These parameters play an important role during the planning process. Your risk management plan is heavily dependent on assumptions. If you failed to properly analyze them, it may affect your project’s outcome.

The assumptions and constraints are an important aspect of your project. Although they are not managed like the requirements or risks, a proper documentation of them helps protect you from many troubles.

You can find your project’s assumptions and constraints in the project scope statement.

Okay, let’s discuss them one by one.


An assumption is a belief of what you assume to be true in the future. You make assumptions based on your knowledge, experience or the information available on hand. These are anticipated events or circumstances that are expected to happen during your project’s life cycle.

Assumptions are supposed to be true, but do not necessarily end up being true. Sometimes it may turn out to be false, which can affect your project significantly. They add risks to the project because they may or may not be true.
Suppose in our shopping example, you assumed that it would take one hour for you to reach the destination. What will happen if due to traffic, you don’t reach the mall on time?

Your assumption is false and your plan for shopping is endangered.

This can also happen to your project. For example, you have made the assumption that some particular equipment will be made available to you whenever you need it. However, when the time comes, the equipment is not available.
Now you are in a difficult situation.

Assumptions play an important role in developing the risk management plan. Therefore, as a project manager you must collect as many as assumptions you can. It will assist you in developing a sound risk management plan.

The following are a few examples of assumptions:

  • You will get all resources required by you.
  • During the rainy season, cheap labor will be available.
  • All important stakeholders will come to the next meeting.


Constraints are limitations imposed on the project, such as the limitation of cost, schedule, or resources, and you have to work within the boundaries restricted by these constraints. All projects have constraints, which are defined at the beginning of the project.

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

A constraint can be of two types:

  1. Business Constraints
  2. Technical Constraints

Business Constraints

Business constraints depend on the state of your organization; for example, time, budget, resource, etc.

Technical Constraints

Technical constraints limit your design choice. For example, let’s say you’re constructing a pipeline, and according to the design your pipeline should be able to withstand a certain amount of pressure. This pressure limit is your technical constraint.

So now you know that every project has constraints; therefore, you must identify all your project constraints (such as any milestone, scope, budget, schedule, availability of resources, etc.), and develop your plan accordingly.

Constraints are outside of your control. They are imposed upon you by your client, organization, or by any government regulations.

There is an interesting fact about the constraints: If the constraints become false or are no longer valid, it is more likely that your project will benefit from it.

The following are a few examples of constraints:

  • You must complete 25% of the work within the first 30 days.
  • You have to work with the given resources.
  • You will be given only two site engineers.


So you can see how important the assumptions and constraints are for your project. An assumption is anything that you think to be true but there is no guarantee, and a constraint is a limitation on you and your project. Assumptions and constraints can be anything; they might be related to human resources, budget, time or any kind of functionally.

Assumptions need to be analyzed and constraints need to be identified.

As a project manager you must analyze how assumptions and constraints affect your project and what will happen if any assumption fails or any constraint gets resolved or turns out to be false. If you handle your project constraints and assumptions appropriately, it will help you deliver your project on time while meeting stakeholders’ expectations.

Here is where this blog post ends, and I hope that you now have a better understanding about assumptions and constraints. If you have something to share, do so through the comments section, and I will be happy to respond your comments.

This is an important topic from a PMP certification exam point of view. You may see a question on this topic on your test.

image credit => renjith krishnan /


  1. Mani Naga says

    I have scheduled for the exam on Jan 20 (3 days back) and got confirmation mail from Prometric center, but when I log on to PMI web site it still shows the status as yet to schedule the exam.
    Do I have to report to PMI or wait for some more days for the status update.
    Mani Naga.

    • Fahad Usmani says

      You got the confirmation email from prometric center, that is enough for now. Once you pass the exam, your status will be changed.

      Anyway, in case of any doubt you’re free to contact the PMI customer care.

  2. km533 says

    Hi Fahad,

    Thanks for your explaination.
    Was going through the Project Scope Statement and found the term ” Product Acceptance Criteria”.

    As per my understanding of this term,it means certain condition/threshold on which the Product/Project will be accepted.

    Can you please explain what is your understanding of this term as per the PMI perspective. If you could give some real world examples related to this it would be even better.


    • Fahad Usmani says

      Let us take the example of iPhone 5.

      Physical dimensions of iPhone 5 are as follows:

      Depth- 7.6 mm, weight – 112 gm and volume – 3.3 sq. inch.

      Now the dimensional acceptance criteria for iPhone 5 may be as follows:

      Depth = 7.6 with tolerance of 0.001 mm (either negative or positive),
      weight = 112 gm with tolerance of 2 gm (either positive or negative) and
      volume = 3.3 sq inch with tolerance 0 .01 sq inch (either positive or negative).

      Now, if any iPhone model is found exceeding the tolerance limit will not be accepted.

      (Note: Above tolerance limits are given for illustrative purpose only. I have no idea about the actual tolerance limit for the iPhone.)

  3. Ola says

    Hi Fahad,

    Thanks as always for your usual assistance regarding Project Management. I’d like you to explain the differences between Constraints and Enterprise Environmental Factors. It seems they mean almost the same thing. Thanks again.

    • Fahad Usmani says

      No they are not the same.

      Constraints are the limitations to your project. For example, you have finish this project within 90 days. Constraints are the limitations imposed on your project.

      On the other hand Enterprise Environmental Factor is an Environment, you have to work within it.

  4. Bernie Atkins says

    Hi Fahad,

    I was going through the meaning of Project Scope Statement but as I am from a Construction Management background, I’m finding it hard to provide a Project Scope Statement on a building for example. PMBoK seems to be more related to other industries. Do you have an example?


    • Fahad Usmani says

      The PMBOK Guide is industry independent. This guide is extensively used in construction industries. I am seeing it in Oil and Gas Field.

  5. John says

    I have scheduled for the exam on Jan 20 (3 days back) and got confirmation mail from Prometric center, but when I log on to PMI web site it still shows the status as yet to schedule the exam.
    Do I have to report to PMI or wait for some more days for the status update.

  6. says

    Thanks you for helping me to understand the terminology. I am working on my ITT Technical Institute Online PM333 class Course Project. I complete the Project Concept as good as I could and submitted it. I am now on my Business Case paper I was need some more example of Assumption and Constraints that will related to my Project topic which is “Redesign Employee Lunchroom (or break room) for a Company.” And to help me visual I went with the local campus for ITT in North Charleston, SC.

    If needed you can read my Project Concept at the following link:

    And if needed you can read the Business Case paper but remember it is incomplete at the following link:

    Any other advice you can give to aid in the completion of the papers (Deadline for all assignment for this PM333 is Sunday Night.

    I still got to work on the Project Charter Paper, Communication Plan Paper, Risk Management Plan Paper, Quality Management Plan Paper, Post-Project Report Paper and something called a Debriefing Report which talk about Lesson Learned in the instruction of the assignment.

  7. Asia says

    Hi :)
    Im interested with your conceptions.. Could you give some examples of assumptions and constraints when the project is about improvement the educational programme..?
    I would appreciate your help :)

    • Fahad Usmani says

      Hello Asia,

      I suggest you contact with some experienced in dealing with this type of projects.

  8. Nadirah says

    Hi.. I attempting to do the first set of documents to create a project to build a 5 stories commercial building as a practice before my actual assignment.. Other than the resources, time and budget constraints what other are there?

  9. Niraj says

    I see that Assumptions and Constraints are part of both the Project Charter and Scope Statement. My understanding is that Assumptions and Constraints both appear in the Scope Statement and are more detailed. These can also be a part of the Project Charter but will be high-level only. Is this understanding correct.

    From an exam perspective should be consider these as a part of the Scope Statement only.

  10. Fatima says

    hi, can you give an example of a project where its scope is contraint, cost is to be accepted and time is enhance. please

  11. Fahad Usmani says

    Predetermined budget, imposed dates, milestones and the product characteristics can be examples of constraints.

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