Brain storming is one of the oldest known methods for generating group creativity. A group of people come together and focus on a problem or proposal. There are two phases of the activity. The first phase generates ideas, the second phase evaluates them. An experienced facilitator is useful.


Although some studies have shown that individuals working alone can generate more and better ideas than when working as a group, the brainstorming activity enables everyone in the group to gain a better understanding of the problem space, and has the added benefit of creating a feeling of common ownership of results.



Brainstorming is done with a group of people, which may be as small as two, but usually no larger than 12. One of the group should be nominated as facilitator. It is useful if the facilitator has had previous experience of brainstorming. The group should be assembled, and the facilitator should explain to the group: firstly the problem or idea to be explored; and secondly, the sequence of events that will take place during the method.

There are broadly speaking two phases:

  1. nurturant or ideas phase
  2. analytical phase.

Nurturant phase

In the nurturant phase, members of the group put forward ideas about the set topic or problem. Be aware of three important issues:

  • ensure that everyone in the group has an equal opportunity to put ideas forward
  • nobody in the group should criticise ideas put forward or attempt to evaluate them in any way
  • all the ideas put forward should be part of a record everyone can see.

Participants may be invited to take turns to present one and only one idea at a time, in a round-the-table fashion. If convenient, post-its may be used as follows:

  • every participant has a stack of post-its
  • participants write down their ideas on their own post-its at any time
  • when it is a person's turn to present an idea, they present the idea on the best of their post-its, and then fix the post-it onto a wall where everyone else can see it
  • post-its should initially be arranged in a haphazard fashion.

Alternatively a white-board or computer may be used: anything that will enable the entire group to see what ideas have been generated so far.

The end of the nurturant phase will be apparent, as the speed of ideas slows down.

Analytical phase

In this phase similar ideas are brought together, and ideas which are impractical or incorrect are modified or discarded. Ideas may be combined and new ideas may be generated.

However, the objective of this phase is to tidy up the wealth of ideas generated in the nurturant phase, and to filter the ideas through the critical faculties of the group.

If post-its have been used, they may be physically moved around and post-its which act as summaries may be generated, perhaps in a different colours. Otherwise coloured pens may be used on the whiteboard to indicate links between ideas.

The facilitator may from time attempt to summarise by recounting the clusters of ideas that have been formed, why the group thinks some clusters of ideas are more promising, and others less..

As the analytical phase draws to a close, the facilitator should attempt to get the group to rank the clusters of ideas in order of priority, promise, or acceptability.

More Information

There are many approaches to brainstorming. Some other resources worth considering are:

Alternative Methods

Focus groups and the requirements workshop are alternative methods which combine inputs from many people in an interactive manner. Critical incidents may also be considered. Brainstorming is a very generic method that can be applied to many situations.

Next Steps

If brainstorming is being used in the early phases of conceptual design a great many ideas will have been generated which will need structuring and will have to be evaluated for technical feasibility. More focused methods such as task allocation, scenarios of use or paper prototyping can be used to achieve this.

Case studies

Clegg, B, and Paul Birch (1999) Imagination Engineering. Financial Times Prentice Hall.

Background Reading

Osborn, AF Applied Imagination. Scribeners & Sons, 1963, NY.

Edward de Bono, Serious Creativity, HarperBusiness, New York, US, 1992.

©UsabilityNet 2006. Reproduction permitted provided the source is acknowledged.