Although it is widely practiced, brainstorming is seldom utilized to its full potential. Over the years I have interviewed scientists, inventors, entrepreneurs, and other creative people from various professions. One of the things I wanted to know was the key to great brainstorming sessions.

I already knew these fundamentals:

• Start with a warm-up exercise - especially if the group doesn’t brainstorm frequently or when the group seems distracted by outside issues. Use word games or puzzles or humor to set an atmosphere that is relaxed, fun and freewheeling.

• Encourage everyone to participate, either with original ideas or “piggybacking” (adding on to) other people’s input.

• Focus initially on quantity, not quality of ideas. Write all ideas on a white board or large sheets of paper and number them to help motivate participants and to jump back and forth between ideas without losing track of where you are.

• Urge participants to say anything that occurs to them, no matter how wild or “far out” those ideas may seem.

• Realize that brainstorming sessions tend to follow a series of steep energy curves. When the momentum starts to plateau, the facilitator needs to build on what’s been stated (“That’s a great idea; now what are some other ways to _____________?”) or to jump to another point (“Let’s switch gears and consider _____________.”)

• Break the brainstorming session into two parts: the first for idea generation and the second for evaluation. During the idea generation phase, no one should be allowed to judge, criticize, or squelch any of the ideas presented.

• Stay alert for nonproductive comments such as, “We tried that last year,” “I don’t think that will work,” etc. and counter premature judgment with, “This isn’t the time for evaluation yet.”

But the best advice I ever received about brainstorming was this: Invite the janitor. Or anyone else who can bring a new perspective to the problem. It’s the diversity of thinking styles, points of view, personal experience, and gut feelings that feeds the creative process. One of the most productive brainstorming sessions I have ever facilitated mixed administrative assistants, lawyers, executives, mail clerks, accountants, and corporate communicators. Their unique capabilities and contributions made the session so much more effective. It would have only been better if we'd thought to invite the janitor!