Brainstorming and Following Through

A recent article in The New Yorker traces the history of brainstorming from its genesis as an idea from an advertising executive in the 1940s. Jonah Lehrer’s story discusses brainstorming’s popularity before dropping this bombshell:
“But there is a problem with brainstorming. It doesn’t work.”

Lehrer, citing University of California-Berkeley psychology professor Charlan Nemeth, says that the standard “no criticism” brainstorming is ineffective because debate and criticism stimulate ideas, rather than inhibiting them. He goes on to discuss different theories on how employee interaction leads to better ideas.
While it’s true that bad ideas can lead to good ones, it’s important to look at those ideas with a critical eye. How does your firm’s brainstorming process work? What techniques have proven fruitful for you?