Clarks definitely runs a bit small.  I'm usually a solid 5 but these were a bit tight.  I think they'd losen up a bit over time but I decided to go up a size only to discover that half a size is a HUGE jump up in size.  Other than the funky sizing, these shoes were really cute. The kitten heels were really comfortable and the rounded (ish) toe made for a nice classy simple look.