Assumption Mapping

Assumption Mapping is a powerful tool for listing and prioritising project assumptions by placing them on an Importance × Certainty matrix. This process helps teams focus on critical assumptions that require testing, thereby minimising risks from the outset of the project. It promotes a clear vision of the product and proactive problem-solving.

Walkthrough

1. 1

   Introduction to the concept

   10 min

   The facilitator begins by explaining the concept of an assumption in the context of a project: 'An assumption is a belief that we need to validate to ensure the project's success.' They then present the Importance × Certainty matrix and its usefulness for prioritisation. Participants are encouraged to ask questions to clarify their understanding.

   Tip — Use concrete examples from past projects to illustrate what an assumption is.

2. 2

   Brainstorming assumptions

   20 min

   Participants are invited to list all the assumptions they have regarding the project. The facilitator distributes sticky notes and pens for each assumption. Participants then stick their notes on a wall or whiteboard. This step allows for visualising all assumptions and ensuring none are overlooked.

   Tip — Encourage participation from everyone by asking each team member to share at least one assumption.

3. 3

   Assessing importance

   15 min

   The facilitator explains how to assess the importance of each assumption: 'What is the impact of this assumption on the project's success?' Participants discuss in groups and assign an importance rating to each assumption. This step helps filter assumptions that have a significant impact on the project.

   Tip — Use coloured stickers to indicate the level of importance on each sticky note.

4. 4

   Assessing certainty

   15 min

   Participants then assess the certainty of each assumption: 'How sure are we that this assumption is true?' They discuss and note the certainty on each sticky note. This step helps identify assumptions that require further validation.

   Tip — Use a simple scale (low, medium, high) to facilitate the rating of certainty.

5. 5

   Placement on the matrix

   20 min

   Participants place the assumptions on an Importance × Certainty matrix drawn on a board. The facilitator guides the group to ensure that each assumption is correctly positioned. This visualisation allows for a clear view of which assumptions need to be tested first.

   Tip — Ensure that each assumption is well understood before placing it on the matrix.

6. 6

   Discussion and prioritisation

   20 min

   Once all assumptions are placed, the facilitator leads a discussion to identify the critical assumptions to test first. Participants discuss the next steps for testing these assumptions. This step ensures that the team is aligned on priorities and future actions.

   Tip — Conclude with a concrete action plan to test the priority assumptions.

Variants

• Use digital tools like Miro or MURAL for a remote session.
• Add a phase for validating assumptions with real data before prioritisation.
• Organise a follow-up session to evaluate the results of assumption testing.