Assumptions and Constraints in Project Management

Assumptions-ConstraintsProject assumptions and constraints are one of the most commonly used terms in the project management and the PMBOK Guide. You must have a clear understanding about these project management terms in order to understand the scope statement and various other concepts.

Keep in mind that, as per the PMBOK guide, project assumptions and project constraints can be found in the project scope statement.

Project assumptions and constraints need to be monitored throughout the entire project life cycle, and can be amended or revised at any time if required. If you fail to pay proper attention to them, it may affect your project’s result. These parameters play a very important role during the project planning process. Moreover, your risk management planning process is heavily dependent on the assumptions.

Assumption and constraint can be anything related to human resources, budget, time or functionality.

Now let us discuss them one by one.


Assumption is your belief or this is what you assumed to be true in the future.  The basis of assumption is your experience, knowledge, and the information available to you.

Assumptions are supposed to be true, and if they happen to be wrong, it can have a significant effect on your project.

Your risk management plan is dependent on these assumptions.  If your assumptions go wrong then your risk management plan may not be as effective as it should be.

Therefore, as a project manager, you must write down all assumptions for future verification and validation. You may also make amendment to it if needed.


Constraints are limitations imposed on the project, and you must work within the boundaries restricted by these constraints. The PMBOK guide recognizes the six project constraints; i.e. scope, quality, schedule, budget, resources and risk.  Out of these six, scope, schedule, and budget are collectively known as the triple constraints of the project.

Every project has constraints; therefore, it is in your best interest to have a better understanding about your project constraints; e.g. any milestone, scope, budget, schedule, and availability of resources. Once you understand your project constraints, you will be in a better position to develop your project plan accordingly.

Usually, constraints are the hurdles during your project execution process. The only way to deal with them is to document them properly and create a plan is such a way as to satisfy all project limitations.

An interesting fact about the project constraint is that if the constraints become false or no longer valid, it is most likely that your project will get benefit from it.

Constraints are outside of your control – they are imposed upon your project either by the clients, by your organization, or by any government regulation.

A few examples of assumptions and constraints are as follows:


  • During the rainy season you may get cheap daily workers
  • You will be provided with all resources required by you


  • You must finish 25% of the project work within 30 days
  • You must work within the available resources

I hope that now you have better understanding about the project assumptions and constraints. Let me know if you have any further queries about them, and I will be happy to respond to your questions.

This is an important topic from the PMP Certification exam point of view. You may see one question this topic on your PMP 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. 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. 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. 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. 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. ishaq ALI says:

    i have still confuse in “CONSTRAINTS” plz i need explanition of these terms..plz help

Speak Your Mind