My parents always respected my privacy when I was growing up hence I learned to always respect others'. Granted, I was an out-of-control teen, but they wouldn't have known unless they followed me everywhere I went. Although I made my mistakes, having their trust allowed me to turn myself around when the time was right for me.
I'm "friends" with my teens on their myspace, facebook, tumblr etc, so I can see whatever their friends see. We have ongoing dialog, so I know what issues they deal with and although I'm not deluded enough to think they don't have their secrets (and so they should), they come to me for the important stuff. I've given them the tools to make smart decisions and they know they have my trust. I believe that the value of my trust trumps security and keeps them honest. They understand that having my trust ensures they must take personal responsibility for their actions.
I've never sheltered them from the real world; they're always learning about consequences. I'm not sure what's meant by "doing what they shouldn't be doing", but isn't that what growing up is all about? When they were younger, I would monitor them when they were online and I still will take a peek over their shoulders, just so they know that I have the option.
