It depends on what you mean by one stance, we are taught one way to stand, but we could have 2 (orthodox or left hand in front and southpaw or right hand in front).
Also some fighters are taught more of a peek-a-boo type stance to that of the traditional boxing stance, some fighters change the way they hold their guard depending on their opponent, for example a smaller fighter keeping his hands a touch higher (or in most cases crouching a bit more) against a taller fighter to protect his head, a taller fighter standing a lot more straight enabling him to use his reach and height over a shorter boxer, tightening you guard against an aggressive opponent etc.
I think I have covered the basic stance in a bit of detail in this article:
http://www.fightauthority.com/forum/...le.php?aid=150
hope it helps
umy