Just guessing here. I recently saw The Jerome Robbins celebration in Melbourne and thought that the choreography of The Cage in particular was so complex that one couldnt just pass on a written list of the steps( e.g. plie with bottom wriggling)for any company that wanted to do it. So must a company employ someone who has danced or taught the steps so that they will be correct each time it is put on? So is it the Repetiteur who fills that role and who works with the ballet master? If this is so, it means that ballet is a little like Zen Buddhism where lineage and the passing of knowlege through the generations is very important.
In other words ballet really is like a religion!!!

A repetiteur is a member of the artistic staff who reports directly to the ballet master, or the Artistic Director in some companies. His job (a woman would be repetiteuse) is to schedule the rehearsals for all the company's repertoire. He may or may not supervise some of them as well.

Thank you. So how does a ballet company learn the steps of a ballet that is new to them or being re done.?

Dancers learn steps almost always by having people demonstrate. The people from the Balanchine and Robbins Trusts, who are sent to stage works, are often called repetiteurs. (I've never seen "repetituese" in a program.)

In Russia, most, if not all, of the dancers, at least the promising and established ones, have a mentor, who coaches them in their roles. For example, in the "Sacred Stage" video, you can see Yulia Makhalina being coached by her mentor, and then coaching a promising newbie.

For a work brand new to a company, unless there is someone in the company who knows the work -- for example, Peter Boal has staged a number of works at PNB that he danced -- someone is hired from the outside. That person (or people) teaches the ballet. Often second and third casts, schedules permitting, will watch these rehearsals and learn from the sides.

Sometimes a choreographer, like Maillot for his "Romeo et Juliette" this year, will send a stager(s) ahead of time, and then will come to work further or fine tune the work.

Another alternative is that a company may have done a piece before, and an internal Ballet Master will set the corps and demi-soloist work, but some of the Principals may have additional coaching sessions. For example, Suzanne Farrell was in Seattle for a few days a couple of years ago, and worked with at least some of the Principals in "Diamonds".

Each stager works differently. Some have muscle memories like elephants. Francia Russell relies upon her notes. A number of stagers who have been at Q&A's, like Russell who used to moderate them, are wary of using video as much more than a memory aid, because they to a last person have said that mistakes creep in, and there's too much risk in following a video blindly.

Not many stagers seem to rely on notation, which is often remarked upon as being more appropriate for modern dance, but Doug Fullingon is an expert in Stepanov notation, and has done beautiful reconstructions from them.

Ballet biographies are full of descriptions of being taught from one dancer to another, from Primas who sought out Karsavina, to corps members who teach each other the roles just before the curtain goes up to cover for injured colleagues.

For re-working, often the company Ballet Masters are responsible for teaching and re-teaching, and there's a lot of peer-to-peer teaching as well. Of course, when there's a Balanchine around, and no one remembers the steps, he might just toss the old version and make a new one

In nearly every pre- or post-performance Q&A I've seen, this question comes up. So you're not alone in wondering.

I'm sure some of the people with professional experience could comment further on their experiences.

Actually, Mel, in French (originally the word is French) a woman would be a repetitrice.
(Edit : even better : répétiteur and répétitrice, complete with accents !)

Is it safe to say that most ballet has been passed along by demonstration/teaching as opposed to some form or written or graphic presentation?

Yes, most passing along of ballets happens in the oral tradition. Today, if a ballet master is not a principal choreographer, a company will either retain an artist for that purpose, or for learning older ballets, hire "stagers" to make productions soundly based on earlier choreography. In the Royal Danish Ballet, they even have a category called "putters-up", who rescue old ballets from oblivion. Stagers may use any number of tools to supplement their memories, and that's a good thing, but for sheer efficiency, there's nothing quite like somebody who's "been there". Doug's work is made very rich by his deep and wide knowledge of both dance and music history. He not only knows the notation, but is very familiar with content and/or style of the works he's reconstructed independent of Stepanov.

(There is no pejorative meaning attached to that "and/or". For someone less informed, Pharoah's Daughter would have been groping around in the dark! There is very little performance tradition of this ballet to guide the modern stager.)

Thank you all. Helene thanks for the long careful explanation. I guess GhislaineThesmar
( Havent got my spelling primer here) was doing the mentoring for Isabelle Guerin in The Dancers dream of La Bayadere.