A common theme I hear when talking to end users or key opinion leaders is that they don't want to divulge their ideas at risk of it being poached. They may be excellent ideas, or forward thinking individuals, but grow concerned about IP/giving away ideas, etc. On the flip side, they often don't have the time or resources to tackle all their ideas (if any) so things don't get done. I speak in particular from a healthcare perspective.
In your mind, how would you convince such users to participate in brainstorming more freely?