Even as kids chafe at limits and discipline, they secretly crave both. By setting rules, you're paying attention to your child's well-being — and that makes him feel loved and protected. You know, of course, that it's your job to set the boundaries even if it means a clash. But how do you go about choosing which battles to pick and which to ignore?

Molly, a mom of four, knows where her lines are drawn. "I think of my kids' behavior falling into three possible categories: the good, the bad, and the ugly." While she thinks of the bad as "uncooperative" behavior, it's the ugly stuff — the risky or harmful actions — that she works hardest to prevent. "Though I try my best not to let everything turn into a showdown, I don't let anything in the ugly category get past me if I can help it. If one of my kids talks back to me, for example, I don't let it slide. Nasty words are hurtful, so I always take a stand against them."

Joanne, mother of 7-year-old Eden, has a different method for sorting out what she calls the "big deals." "To decide what's over the top for my child, I ask myself one simple question: What will this mean for her when she's thirty? It helps me put things into perspective and decide if something's really worth the fight. For instance, when Eden started preschool, she had a favorite shirt. I couldn't peel this red turtleneck off her back — so I stopped trying. Instead, I told myself, I'm sure at thirty, she won't be wearing the same shirt! On the other hand, I insist that Eden sit in the back of the car and stay buckled in — no exceptions. As far as I'm concerned, buckling up means she'll be alive at thirty, so it's worth the fight."