Group methods (compared to individual ideation):
- Produce significantly fewer ideas
- Generate ideas of lower average quality
- Produce fewer of the very best ideas, and
- In addition, groups are not effective at evaluating or ranking generated ideas.
Add-on ideas building on others ideas were generally lower quality than individual ideas. In short group ideation stinks.
My summary may be too kind… Stop killing ideas and wasting time!!
ProfessorGary on Innovation and Marketing 
I have always thought it best to preface group ideation with the requirement that people spend some time before hand doing individual ideation. Then these ideas are all brought together and made better by input from others.
In your experience, has this not worked effectively?
Individual brainstorming before the group sessions should help reduce the idea devastation from the group dynamic — always do it! However the group effect still comes in. Unfortunately research has shown groups to be less effective at combining and evaluating ideas as well as initiating them. However the pre-group ideation is clearly a vast improvement.
Hello, I am very interested by the research you mention about group ideation being less effective. I have always been convinced that groups would bring more than individuals, if there are the right facilitation and moderation techniques (such as De Bono 6-hats for instance). Evidence for or against this is very valuable. Thanks. Yael
One technique that combines the benefits of both groups and individuals is brainwriting – work in a group (benefit of the greater diversity of knowledge, the building blocks of ideas) by having everyone write their ideas on a sheet of paper and passing it in one direction at set time intervals. I have done this in many classes and although certainly not a controlled experiment one particular example is good. Students were individually brainstorming ideas for starting a new business in various clean tech industries. The students struggled with ideas. When instituting the brainwriting exercise students’ lists went from just a few ideas to an average of 50 each – with only 7 students in the class each spending only 5 minutes per students’ list.
But here is a more important thing to keep in mind – the ideas generated in a brainstorming session at not final ideas. That is the case whether they come from individuals or groups. The ideas for new products or businesses evolve from the outcome of the sessions and combine with future ideas. Think of the brainstorming not as an end goal but as a way to increase raw material input for much better ideas. The key is iteration.
Brainwriting is clearly an individual act. I suspect – based on past empirical evidence – that good ideas are generated in the early writing phase and that some are killed in the group evaluation. But I would certainly urge everyone to start any group ideation exercise with Brainwriting!!!