Moms of teens

Mom's of teens, how do you deal with high school parties? I'm not necessarily meaning how do you deal with them after they've already happened but do you allow your child to go to them? Do you think they'll do it behind your back? My teen and I are very open with each other and he's recently asked of he could go to one. I know he has good friends who have good morals and I've raised him to be honest and know he's strong enough to not cave to peer pressure (he's been tested in the past by some bad people he thought were friends and called me immediately) but obviously I'm still kind of worried