#3-#5

3. Ask the experts only

For generating truly innovative ideas, deep expertise in a field can actually be a drawback. In a brainstorm, we’re looking for breadth. Cross-pollination from seemingly unrelated fields can lead to authentic breakthroughs. 

4. Go off-site

By conducting off-site brainstorming sessions, you only reinforce the concept that great ideas only come on the beach or at high altitudes — not in the proximity of your daily work. 

5. No silly stuff

Don't just invite ideas to result in something the firm can market. Wild ideas need to be welcome. Brainstorming should be fun.