The best known and most used group conversation method for generating new ideas is "brainstorming." Ever since 1953 when advertising executive Alex Osborn published his book "Applied Imagination," his brainstorming technique has been used by organizations of all types. (I myself have facilitated dozens of brainstorming sessions, most them fun - but probably not as productive as other methods.)

The two basic principles of brainstorming are 1) defer judgment and 2) reach for quantity. The intended result? A group generates many ideas that can be sorted out afterwards.

However, "There's just one problem with brainstorming: It doesn't work." So wrote Jonah Lehrer is his book, "Imagine: How Creativity Works" (March 2012).

Psychology professor Keith Sawyer, a creativity expert at Washington University, summarizes studies of brainstorming: "Decades of research have consistently shown that brainstorming groups think of far fewer ideas than the same number of people who work alone and later pool their ideas." 

 OK. What are better techniques than brainstorming? 

 Apparently, it's criticizing and debating ideas while generating them, or debating ideas when you come together to pool ideas individuals have come up with. Professor Charlan Nemeth at U.C. Berkeley found groups that debated generated 25% more ideas than standard brainstorm groups. She says "Our findings show that debate and criticism do not inhibit ideas but, rather, stimulate them relative to every other condition." Why? Criticism encourages us to fully engage with the work of others while the "no judgment" condition may be fun --but not so engaging. 

 One newer technique I've used is "Brainwriting," in which a facilitator asks all group members to write down 3 ideas in brief spurts, then share their ideas on paper with one other group member. Traditional brainstorming allows only one person to speak at a time, but brainwriting requires everyone to write ideas simultaneously, then to share their ideas at the same time. For details, visit this site: http://www.mycoted.com/Brainwriting 

Another: Have group members work apart individually, then pool their ideas in a meeting to find the best ones with discussion and debate. Key insights from research: People are not as criticism-averse as Alex Osborn believed and 2) lively debate stimulates more and better ideas.

Examples from popular culture: Beatles John Lennon and Paul McCartney had a combative relationship that inspired them to create greater music. Apple Computer's Steve Jobs was never satisfied with "good enough," was highly critical in design meetings, and encouraged his employees to be critical as well.

My counsel:  Don't continue using brainstorming when alternative methods have been proven superior.