I copied this into my notes some months ago, so I sadly don't have the source. It's good advice:
- Every meeting must have one clear decision maker. If there's no decision maker -- or no decision to be made -- the meeting shouldn't happen.
- No more than 10 people should attend.
- Every person should give input, otherwise they shouldn't be there.
- No decision should ever wait for a meeting. If a meeting absolutely has to happen before a decision should be made, then the meeting should be scheduled immediately.