Tools and Training 
Affinity Diagram

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What is an affinity diagram?
How do I draft an affinity diagram?
Examples of affinity diagrams
More information

An affinity diagram is a method of brainstorming, in which seemingly random ideas or suggestions are eventually organized within natural groupings.

• Affinity diagrams are a great way to organize a large volume of ideas that might otherwise seem overwhelming.
• Affinity diagrams also allow a group to make connections between ideas, or realize recurring themes, in ways that might not seem obvious at first.
• Affinity diagrams can help groups reach consensus by organizing ideas into clearer, easy-to-understand themes.
• Affinity diagrams can also allow team members to complement each other's knowledge in brainstorming; each member of a team or group can contribute ideas to the best of their knowledge, even if they don't know or understand the full scope of the problem.

1. Clarify the problem

Start by drafting a problem statement, or clearly defining the issue to be discussed. Write the issue down, and post it where everyone can see it and refer back to it.

2. Brainstorm ideas

Start generating ideas using the principles of brainstorming. Do not start grouping ideas yet, or allow team members to group ideas. At this point, your team should feel free to state any and all ideas, piggyback off of each other's ideas, and be prepared to suspend judgment on an idea's merit for the moment.

Record ideas on Post-It™ notes, and post them underneath the problem statement.

Note: A typical affinity diagram can have anywhere from 40 to 100 ideas. Don't be afraid of volume at this point—many ideas may eventually be combined with one another if they're similar, or discarded if they're unreasonable.

3. Group ideas

Start grouping the ideas, without talking. (Grouping silently allows team members to avoid influencing each other's decisions, or voicing judgments about ideas.)

When grouping, think about similarities and connections. Some ideas might not fit into a group, which is just fine--sometimes, these "loner" ideas can just as important as other ideas without fitting into a group.

4. Categorize and get consensus

Start talking with each other: Do you notice interesting patterns? Things that should be changed/rearranged?

Place headings at the top of each like grouping of ideas. It's not unusual to come up with 4-5 main ideas, under which ideas are grouped. If you need to, you can divide big group headings into smaller subheadings for clarity, or place two headings next to each other, under a 'superheading.'

5. Finalize

Using an appropriate software (like Microsoft Visio or Bubbl.us), or drawing by hand, finalize your diagram and distribute it to team members as appropriate. Make sure your problem statement is included at the top of your finalized diagram, and that headings and subheadings are evident and reflect the group's consensus.

What is an Affinity Diagram?
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What is an Affinity Diagram?
American Society for Quality