It’s far too easy for kids to assume that private online communication stays private. It feels intimate, and sharing intimate details is one way we build close relationships with friends and love interests, which is part of the developmental work of adolescence.

But teenagers should know that any private exchange of words or photos online can also be shared with the whole school, not to mention the rest of the world.

The reality is that privacy settings and trusted relationships are no match for the temptations and potential for accidents inherent in the technology.

This is why, challenging as it might be, it’s important to talk to kids about sexting, whether it involves sharing provocative pictures of themselves or provocative messages.

As parents, you can avoid being dismissed as nagging, old-fashioned or clueless by not focusing on how you feel about the appropriateness of sexting. Instead, the message should be about the concrete dangers and serious short- and long-term consequences of online missteps.

Here are a few suggested warnings for your kids:

1. Images have a life of their own

In this digital age, information is far less secure and more fluid than it once was. Example: Your daughter may trust her boyfriend with her photos but he, in turn, might trust a close friend who may think it would be fun to share them. Or she may have an enemy who, once in the loop, could go for maximum destruction. Or the phone may end up in someone else’s hands—like the school principal. These are all scenarios that have played out in cases so damaging to young lives that they hit the news.

2. Sexting could result in a criminal record

It is illegal to distribute child pornography, and someone who’s underage can be charged with distributing child pornography, even if she is disseminating photos of herself. So can the boyfriend or girlfriend who shares the pictures with someone else. Remind your children there are laws that govern their actions and they may face serious consequences if they are caught. It’s happened to other kids.

3. Dignity is worth protecting

Remind your child that she cares about how the world sees her. While she might think she controls her own sense of dignity and privacy, sexting takes that control out of her hands. She may think it’s parental paranoia for you to say that wayward pictures can come back to bite her, but you can offer real scenarios: What if they came up during a job interview or when she’s in future relationships?

4. Think before you act

Finally, ask your child to think carefully about what she shares with others. It’s up to her to make good decisions for herself, but, as her parent, and someone on her side, it’s your job to try to help her avoid mistakes that could cause her serious misery. Sexting is one of those things that, done casually, can have very painful consequences.