List, Is there a standard in the industry for piano key width on the naturals.  Nearly all the pianos here are at 23mm except for the five Mason and Hamlins from the 20's we have which measure 22mm giving them a disconcerting space between the keys. Think of David Letterman <G>. We have no European pianos so I can't measure them. One of our piano professors is doing some kind of research paper and was a big advocate for one of our practice Steinways to have a 7/8th keyboard installed for small handed students.  (It hardly ever gets played!) Thanks Paul