I think there's no such thing as the best age to start. It really depends on girl's psychique and other factors. But I agree with you about the certain rule that should be introduced, like not putting a model in a see-through clothing on the runway if she's under 16 (if not 18). I found it weird that Tanya D. had to walk the Dior runway at age 15 in a see-through dress Anyway, I guess if I had to choose the best age to start.... it's probably 15-16 (to do modelling as a part-time job, during weekends, holidays etc.) and then do it full-time when you're done with high school. Then again, some of my favourite models didn't go to high school, they just would have to pass subjects every few months without going to school regularly.... I somehow admire that as I can't imagine I could handle modelling and school with GOOD grades.