Making mistakes is part of being a parent, and discipline is an area where we slip up constantly. It's one of our most daunting tasks, and to do it well we have to make clear, sensible, big-picture decisions at exactly the same moment when we are angry, frustrated, or embarrassed. And that's just as hard as it sounds.

After 17 years of being a mom and a pediatrician, though, I've been able to learn a lot about discipline from my own experiences, and from other parents. While there are all sorts of possible blunders (like the time I forgot I'd left my daughter Natasha in time-out), here are five biggies that most of us are guilty of -- and ways to avoid these common mistakes:

1. Thinking that one style fits all

This one's not surprising: The bookstores are teeming with manuals, each touting an expert's best -- and only -- method. Friends and Grandma love to tell you what worked for them. And there is definitely something appealing about the simplicity of a one-approach-fits-all strategy.

But some children freak out when you speak to them sharply, while others are unaffected. Some learn the first time you tell them something; others need so much repetition, you despair of their ever learning. Some listen right away; others need time to scream it out before you can talk to them.

And it's not just temperament; it's age and development. The job of a toddler is to push limits, to do crazy stuff that you've told him time and time again not to do. The job of a tween is to start asserting her independence from you, in sometimes obnoxious ways. And neither one is going to listen to a big lecture. A toddler is going to need simple, direct, quick discipline. A tween is most likely to respond to a punishment that removes her from her peers. But despite your best efforts, both the toddler and the tween are likely to keep doing the same bad thing for a while. Understanding where they are in life is key to picking the right approach to discipline, and preventing desperation (yours).

2. Overdoing it

My husband does this a lot. He has a way of getting in a bad mood when the kids are fresh (imagine that!), and he metes out punishments that are either more reflective of his mood than the crime or thoroughly unworkable, like saying "You have to stay in your room this afternoon" when he has errands to run and needs to bring the kids with him. The punishment should fit the crime, not your frustration level. And it needs to be something feasible, that doesn't overly affect siblings who've done nothing wrong.

A friend taught me a great trick. If one of the kids is doing something he shouldn't -- being mean to a sibling, for example -- I say, "There will be consequences." (It's particularly good to use in public, because while it may strike fear into your kids, it sounds pretty benign.) Over the years, it's been shortened to "Consequences!" with the appropriate firm-but-not-yelling voice, furrowed brow, and I'm-totally-serious gaze.

If the misbehaving child doesn't stop, there are consequences, but I have a moment to think about them. Sometimes I'll ask, "What do you think your consequences should be?" It's interesting how often kids come up with a fair punishment (e.g., apologizing and letting the wronged sibling play with his favorite toy for the rest of the day).