The NHK Method was developed by Hiroshi Takahashi (author of The Creativity Handbook) during his years working for NHK.
Each participant writes down five ideas on five separate cards; Gather into groups of five (this is the traditionally recognized optimum number for group work in Japan); While each person explains their ideas, the others write down any ideas that come to mind; Collect, sort and line up cards. Group them into related themes; New groups of two or three people are formed – themes are brainstormed for half an hour while participants continue to write down their ideas; Groups organize ideas into themes and announce them to the whole group; All ideas are written on the whiteboard; Participants form groups of ten people and all ideas on the whiteboard are brainstormed one at a time.
Source: Tatsuno, S. (1990). Created in Japan: from imitators to world-class innovators.
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