I'm a women's 5.5-6, and I often buy children's shoes in 3.5-4. I purchased a 4 in these, and they were way too big. I exchanged them for a 3.5, which is the correct length, but was a bit narrow at first. I thought I would have to return them, but they stretched out after several uses and now fit perfectly. I have average width feet, so if yours are wider you might have some problems.

Other than the odd sizing, I love these! They're high quality leather, and you can't beat the price (especially compared to the adult version). They're very comfortable--my only complaint is that the arch support is minimal, but if you have high arches you can always put insoles in. I expect these to last a long time and would recommend them!