I'm pretty lucky. Had 1 bad parent thus far. The core of the team has been together now for 5 years. The first 2-3 years I always had a set of player rules and a set of parent rules that they had to sign. Most of what I have seen is trying to coach from the stands... of course since we've been together so long now, I just tell the parents to SHHHHH, zip it.... but that doesn't even happen very often anymore.