What Mother Goose said.

We will take the stance my parents took with me. No Alcohol if you are under 18! Having one small glass of Champagne at a wedding if they are 16 or 17, if they ask would be considered on its merits (and my knowledge of the kid) but otherwise it is not something I would condone and certainly not allow social drinking occur with my knowledge.

BUT if my kids are anything like me, they will still drink, so I will educate them about alcohol/drugs as well. And make sure they are aware that if they are in a situation where themselves or a friend are drinking and they are also the driver, they should be calling me at anytime to pick them up instead. I won't be happy about the drinking, but it will go down alot better and I would want them to be safe.

I think parents fall into this trap of thinking "well if they are allowed to drink at home, at least I know where they are and that they aren't doing anything stupid." The truth is however, that that is true when they are drinking at home, but it is the drinking aways from home that is the biggest problem. And they ARE still going to do this regardless of whether they drink at home or not. IYKWIM. You cann't supervise teenagers ALL the time.