well, you see if you raise the child right, and take the time and consideration to teach them little by little about the world, and why people do certain things, then even as a young child they can be intelligent about the world. to me, i see drugs as just an object, like getting a birthday present, or smoking a cigarette, it can make you feel good for a while, but like eventually you either: 1.get sick of it or 2.become an addict (obsessed with shopping, addicted to cigs, etc)
somehow my best friend was always able to be honest with her mom (yeah it was like a dream world) and she would party n shit, but was always responsible because there was no reason to sneak around and be 'dangerous' about shit.
she stopped smoking years ago, and drinking.
i dunno, i know many psycho parents that have done ALL OF THE ABOVE(what everyone else posted) and i have never seen positive results of them lol.