At what age did you (or would you) allow a child to fly alone?

If she'd be accompanied to the gate and everything its sounds like there's no way of some type of mix up (wrong plane, missing the flight, etc.) So in that case i think it'd be fine at just about any age. But I'd say like 10 or 11 would be an ok age. But I could justify younger. Depends on every kid individually. If she's younger, but responsible, I don't see an issue.