I found this shoe to run short.  I usually wear a true European 40, US 9.  Originally I ordered that size, which was too short.  Then I ordered a Euro 41=US 10, which fits with the medium weight socks I now plan to wear with it.  I guess I would say that it runs a half size short.  The style of the shoe is very attractive with soft leather and a good heel height for casual or slacks at work.