Just an observation here: Are you looking for the difference between a secretary and an administrative assistant, or an executive secretary and an executive assistant? At least in the U.S. (and here in Spain where I have been both an executive secretary and executive assistant), an administrative assistant is a lower level administrative staff member who usually helps a full-fledged administrator with his or her work. An executive assistant, on the other hand, is generally an executive secretary freed from certain tasks (such as taking minutes) and responsable for, or included in, other tasks (research, brainstorming sessions, etc.) Sometimes "executive assistant" is just a glorified title for a secretary. See:
http://www.wisegeek.com/what-does-an-executive-assistant-do....