How to Identify Assumptions

by Doug Couvillion, former Impact Makers’ consultant


As we move about our day we constantly face unknowns.  To get past these uncertainties we make assumptions.  The assumptions we consciously make are usually not so dangerous because we are well aware of them.  It is the assumptions we don’t recognize that most often get us in trouble.  In the Three Stooges episode Three Little Pirates, Moe, Larry, and Curly are sentenced to death by an angry Governor.  When they plead for leniency the Governor shows his compassion by asking how they would like to die.  Curly quickly replies, “That’s easy, old age.”  This line gets a laugh simply by highlighting the vastly different assumptions made by Curly and the Governor.  In this article we consider several types of assumptions and suggest a few techniques for identifying them.

Types of Assumptions

There are many different types of assumptions in the business world.  Four discussed here are assumptions around:

  • responsibilities,
  • availability of resources,
  • priorities, and
  • constraints.

This list is not intended to be comprehensive but it provides a good starting point for identifying other types of assumptions you may regularly encounter.


Very simply responsibility assumptions are those we make about the responsibilities of others with whom we interact.  Most teams that have been together for a while know the responsibilities of each team member, although they may not be documented or clearly articulated.  These assumptions can cause problems when something disrupts the normal workflow of the group.  It could be a new project, a reorganization of the team, or even the temporary absence of a team member.  The next time a coworker announces he will be on vacation, ask yourself if it is clear who will handle his responsibilities while he’s gone.

Availability of Resources

Resource assumptions are those we make about the availability of key resources when we need them.  These can be related to human resources, financial resources, equipment, software, vehicles, tools, electric power, office space, vendor supplied products or services, and many others.  If your project requires special equipment or a key person, are you sure that resource will be available when you need it or are you just assuming?


Priority assumptions are the guesses we make about which goal or activity should be addressed ahead of others.  Misaligned priorities can be a major source of conflict.  Unfortunately priorities are often set based on many other assumptions.  What is the goal?  How do competing priorities influence each other?  What is the impact of succeeding or failing in one activity over the other?  What’s the strategy for reaching the goal?  Given the number of factors that influence priorities, it is easy to see how two people are likely to make different priority assumptions.


Constraint assumptions are our best guesses about the things we cannot control.  They can be related to deadlines, budgets, or even methods for getting work done.  One of the most stifling assumptions of all is the “we should do it the way we’ve always done it” assumption.  It kills creativity and innovation but people are rarely fired for doing what’s always been done, so this assumption is often used as a safety net.

Identifying Assumptions

Now that you’ve got a starting point for classifying assumptions, you can begin to actively identify them.  Here are a few techniques for ferreting out those assumptions you weren’t even aware you made.

 1. Write down your approach

If you are working on a project or a new assignment one of the best ways to find your hidden assumptions is to write down your approach and discuss it with a co-worker, client, or manager.  By documenting and then explaining the approach, you subject it to another person’s assumptions.  Quite often you will identify assumptions made by you and the other party.  By talking through them you may be able to determine which assumptions are low risk and which require some attention.

 2. Conduct plan walk-throughs

When planning complex, inter-related activities, such as software deployments or office moves, walk-throughs are great for uncovering assumptions.  In a walk-through, the participants review the steps of the plan in the order they will be executed.  At each step they discuss what they will be doing.  This technique commonly uncovers assumptions about responsibilities and the availability of resources.

 3. Question everything

Another technique for discovering assumptions is to regularly question those ideas you believe to be true.  Simply ask yourself the following:

  • Do I know this for a fact or am I making an assumption?
  • If I believe this is a fact, what was the source of information?

If you can get into the habit of regularly asking these questions, you will be surprised at how often you discover assumptions.

Once an assumption has been identified it can be treated properly.  Ask yourself what the consequences will be if the assumption is incorrect.  If an incorrect assumption will be costly you can take the necessary steps to validate it.  Assumptions that cannot be validated can be treated as risks.  For example, if your company is planning the release of a new service, one of the assumptions might be “25% of existing customers will enroll in the new service.”  Since it’s a new service the assumption is nearly impossible to validate.  In that case, treat the assumption as a risk and determine how to handle it.


Although assumptions are often necessary and useful, bad assumptions can turn the best plans into miserable failures.  The problem is we often don’t recognize the most critical assumptions we’ve made.  By consciously looking for assumptions we improve the odds of identifying them and can handle them accordingly.

The Impact Makers Difference

Impact Makers is a management and technology consulting company based in Richmond, Virginia. We provide Project Management, Business Process Improvement and Healthcare/Medical Management Strategy and Implementations. We are a for profit company but we have no shareholders and contribute our profits to local, healthcare related charities. Impact Makers ranked 360th on the 2012 Inc. 500 List of Fastest Growing Private Companies in America. A founding Certified B Corporation, Impact Makers also was named a 2013 Best for the World Company for Overall Impact.