An affinity diagram is my favorite brainstorming tool. It is one of the two quality improvement tools I would drag along if I were stranded on a desert island (the other being a process map). I’d be making coconut radios in no time!

Castaway on a tropical island
Photo by Rowan Heuvel / Unsplash

In its simplest form, the affinity diagram has two steps: 1) free form brainstorming that is 2) later sorted into thematic groupings.

In other words, it gives your subconscious a chance to spawn interesting ideas which you then can sort into rational categories. This illuminates the broad strokes of the critical issues at hand while preserving actionable detail. My teams have used it quite effectively in healthcare-related quality improvement. I have also used it to help me think through some world-building concerns in my writing.

Most recently, I applied the affinity diagram to help me think through the implications of my protagonist’s socially isolated upbringing.

Looking Out A Window
Photo by Alexandre Chambon / Unsplash

Because of specific vulnerabilities, it was not safe for this character to be out in the world, so she spent her childhood homebound. When she is an adult, she must work with a team. How would this history influence her present-day social interactions?

Since brainstorming is most effective when done with others, I asked my writing partner Karen to help me brainstorm about this.

Here is how we made our affinity diagram and insights we gained about my character.

Generating an Affinity Diagram

Step One

Karen and I discussed the purpose of our activity for a few minutes to ensure we were on the same page. We decided we wanted to know what the impact of having a socially isolated childhood would be on an adult who finds herself regularly working with a team of people. What happens when she is trying to interact?

Step Two

We each silently brainstormed by independently writing our ideas onto sticky notes. Only one idea went on each sticky note. We kept going until we ran out of ideas.

Step Three

We spread our stickies out on the table, randomly mixing our notes together. In my old life, the sticky notes went on a conference room wall. In this case, since Karen and I have our weekly writer’s meeting in a bar, the stickies went on the table. Of note, I was trying to use up some old heart-shaped stickies. I was not trying to be cute. (Ugh.)

Karen and Amy’s Brainstorm Sticky Notes

Step Four

We grouped the sticky notes into thematic groups silently, only speaking to clarify the meaning of sticky notes as needed.

Karen Considers Our Thematic Groupings

Step Five

We negotiated the titles of the thematic groups.

The Four Thematic Groups
Self-Centered Theme with Detail

Step Six

After reducing redundancies, I typed up this information to use as a character-building tool for my story.

Final Affinity Diagram Output


The exercise with Karen was a simplified and informal use of a potent quality improvement tool. Yet, it yielded just what was needed for our purposes. It was fun too!

If you are a quality improvement friend of mine, then you should read more about Affinity Diagrams and remember these key points:

  1. This activity allows the team to synthesize and find relationships between granular bits of information. This leads to a broader understanding of an issue while maintaining actionable details.
  2. This form of silent brainstorming allows the introverts on your team space to contribute.
  3. The silence also minimizes the impact of dominating personalities/influential people.
  4. The anonymity (when done in a group) makes it safer for front-line participants to share their honest opinions.