Parents who set limits show love and demonstrate that they are in charge, experts say.

But it's important that parents and teens listen to each other and, when possible, compromise.

"When I was little, I always wanted my ears pierced," says Nick Tondra, an Indianapolis high school junior. "I just thought it was unique."

His request started with the ultimate — for both ears to be pierced. When his mom said no, he asked to get one pierced, and she agreed.

"Afterward, she realized it wasn't that big of a deal," Nick said, "so eventually she agreed to let me pierce the second ear."

His mother, Liz Tondra, 49, says she chooses her battles.

"It's certainly not what I would have wanted for him, because my generation sort of frowns on guys piercing their ears," she says. "I have to remember that in every sense of the word, Nick is a conservative kid. This is just a trend."

Nick carries a 3.5 grade-point average and plays varsity hockey. Adopted by the Tondras at 15 months, after he was orphaned in Mexico City, he recently was invited to Washington by the Anti-Defamation League and is a mentor at his school offering peer education on diversity.

Nick's sister, Abi, 20, a junior at Indiana University majoring in photography, has her ears, nose and tongue pierced — and her earlobes stretched.

"This was part of trying to find my spirituality, like a rite of passage into adulthood," Abi says. "It's like some girls wearing high heels and makeup."

She was 18 and away at college. She sent e-mail to her parents after the fact.

"She's a good student, a wonderful kid who has taken a different avenue to self-expression," says her mother. "She's going to have to deal with how people view her."

In the Tondra family, a non-negotiable issue is tattoos.

"I think I'm more liberal than some parents," Liz Tondra says, "but I draw the line with things that are going to cause major damage to the body or could result in medical bills."

Some parents choose to lead by example and then let teens test the waters themselves.

"Setting limits is about building character," says Olgen Williams.

Williams, who works with at-risk youth, tells young men who come to him seeking jobs to remove their hats and pull their pants up to their waists.

"Setting ground rules when it comes to appearance isn't always popular, but it shows respect for others," Williams says. "They have to realize society has a norm."

Some parents believe that setting limits will destroy closeness with their kids and take all the fun out of parenting, said Dr. Dan Kindlon, author of "Too Much of a Good Thing" (Miramax, $13).

Even though mutual respect is important to a healthy parent-teen relationship, Kindlon says it's not a bad thing for parents to assert power over children when it is in a child's best interest.

Williams had his own challenge with his 17-year-old son, Aaron, who favored the look of baggy jeans, " 'do rags" and boots.

The high school senior says he had a run-in last summer with an acquaintance wielding a gun. Aaron changed his ways and, ultimately, the way he dressed.

"To a certain extent, I was involved with the wrong crowd," says Aaron. "I needed to make an inward change, and I wanted it to show on the outside."

Now, he wears button-down shirts, ties and khakis to school.