My 10-year old son is tall and slim. Because he is tall for his age, I ordered him a size 12. The length was perfect but the waist was close to three inches too small! The proportions are WAY off on these pants. That said, they are thick, well made pants. I am returning them and ordering a size 14 (ridiculous given that he's 10 and so slim), but again, the sizing for these pants is way off.