Assumption mapping

What is it

Assumption mapping helps individuals and teams identify and mark out the assumptions they have about a specific topic or project. Assumptions are the things we take for granted and by identifying and mapping them, we can make sure were all on the same page and understand each other. It also helps us identify and priortise things later as well. As some of the assumptions we have may be optimistic or what we expect to happen but don’t know yet.

An assumption mapping workshop is designed to facilitate discussions and help teams make better decisions by understanding the underlying beliefs and thought processes that drive their actions.

When to use it

Assumption Mapping is an effective tool for a wide range of topics such as new product development, business strategy, or social initiatives. It is particularly useful when:

  • you’re facing a complex problem or decision-making process and you want to identify any potential roadblocks or challenges that may arise
  • you’re joining a team or starting an initative and want to gauge what you and the team know and believe to be true
  • you want to structure all the things you’ve learnt or heard from other initatives and stakeholders before doing further research

Assumption mapping doesn’t just have to be used at the beginning of projects. Thought they are very useful then. You can use them whenever you want to get a sense of what you know and believe to be true.

How to do it

In a workshop

Bring together your team with an 1-2 hour block of time together. You can do an assumption mapping workshop online or in-person.

  1. Begin the workshop by introducing the concept of assumption mapping and its purpose. Explain that assumptions are the things we take for granted and that by identifying and mapping them, we can better understand our underlying beliefs and what we believe to be true. Things that’ll drive all our decisions and actions.
  2. Depending on how many people you have you may want to divide participants into small groups (No more than 5 people). With a facilitator for each group. If there are less than 5 people, stay in 1 group
  3. Give each group a space to brainstorm their assumptions. This can be a flip chart paper and markers, a google doc or something like a miro board. Giving the team a sensible time limit (think 5 minutes). Ask each group to brainstorm a list of assumptions they have about a specific topic or project individually
  4. Once the list is complete, have each group share their assumptions within their group. Making sure they write each assumption on a note and place it on the wall or whiteboard. Removing duplicates and placing similar ideas close to each other.
  5. If you’ve split into smaller groups, return to the whole room and get each group to share their assumptions. Create a consilidated list of assumptions as you go along.
  6. With the whole room together, sort the assumptions into categories (e.g. assumptions about technology, assumptions about people, etc.). If the groups are too large to do this together, portion sections for different groups to tackle
  7. Using the categories, create a visual map of the assumptions on the wall or whiteboard. This can be done using lines and arrows to show relationships between assumptions. Or by bunching them together with headings. If this is in person, make sure people get up and get involved in this process.
  8. Next, have the group prioritize the assumptions by discussing which ones are most important to address. When preparing think about how and against what you want people to priortise against. You may also want to use a structure like a 2-by-2 framework with the dimensions of certainty and risk
  9. Finally, discuss next steps for addressing or testing the assumptions that were identified. You can also use a 1-group-room loop where you get people to generate ideas individually, then in pairs or groups and if needed to the wider room. If you’ve run out of time to do this. Make a promise to do it as soon as possible.
  10. End the workshop by summarizing the key takeaways and action items from the discussion.

Related techniques

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