The affinity diagram is a business tool used to organize ideas and data. It is one of the Seven Management and Planning Tools . People have been grouping data into groups based on natural relationships for years; However, the term affinity was devised by Jiro Kawakita in the 1960s  and is sometimes referred to as the KJ Method .
The tool is widely used within the framework of management and allows for large numbers of ideas stemming from brainstorming  to be released in groups, based on their natural relationships, for review and analysis.  It is also frequently used in contextual inquiry as a way to organize notes and insights from field interviews. It can also be used for organizing other freeform comments, such as open-ended survey responses, support call logs, or other qualitative data.
The affinity diagram with the following steps:
- Record each idea on cards or notes.
- Look for ideas that seem to be related.
- Sort cards into groups until all cards have been used.
Once the cards have been released, they can be used for large groups of subgroups for easier management and analysis.  Once completed, the affinity diagram can be used to create a cause and effect diagram . 
In many cases, the best results are achieved when the activity is completed by a cross-functional team, including key stakeholders. The process requires to be deeply immersed in the data, which has benefits beyond the tangible deliverables.
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