How often do you feed your dog?

I always understood that adult dogs just needed one meal a day and puppies more often. That's what I've always done with my dogs.

I know there's aschool of thought that says you should fast a dog for one day a week. I don't think I would ever be able to bring myself to do that though. My dogs always know when it's feeding time and I would feel cruel depriving them of the meal they were looking forward to.