My daughter is in a private school that requires the Sperry Top-Sider 2 eye Boat Shoe.  We ordered a size 9 to replace her size 7's purchased last year, that were just too small.  Well the size 9's were the same length and width as the size 7 shoes, and still too small, her foot would not fit in the shoe.  So I returned the shoes for a full refund, which was nice, I just had to pay the shipping and we ordered a size 10, which is way to large for her foot.  I don't understand. Two years ago we went to a store and got her a size 7 which fit for 20 months, then she really out grew it, we went to the same store and tried on an 8, 8.5 and finally the 9 fit the best.  Then we ordered it on line and her foot would not fit in the shoe...  With two pairs of the required school socks the size 10 will stay on her feet.... I just don't understand.....The folks at Sperry could not explain it either...  So beware of ordering the shoe on line, the shoe may say it is a 9, but in reality is only the same size as a 7....  The company was very nice about the whole issue..... but why were the shoes so different in size?