At what age do you think children at allowed to make their own decisions and be responsible for those choices? Now I know this is a sliding scale depending on the request/desire. For example, I would think that most people would have a different opinion on, say, what to wear that day verses medical care--- two things that are on extreme ends of the scale.
However, as a general rule of thumb at what point does your job as a parent change from micromanaging their life to something less controlling? Do you have different ages based on the subject i.e.food choices, personal privacy, homework etc.