This is my first pair of Birkenstocks.  Given my foot size (women's size 11), I have a hard time finding them in stock in stores.  I am really a size 10.5, but usually get an 11.  I bought an 11 in these, and they fit perfectly.  I'm still in the breaking in process, and hoping they conform.  They are long enough and fit perfectly for width.  The ankle strap could be longer, in my opinion.  I have it on the 2nd to last hole.