Ethics... the more I read the more I think its mainly common sense. I understand it is more complicated than that and certain principles must be followed, but my basic understanding is being an honest, moral human being = an ethical one!
My professional practice at the moment is mainly auditions, so I've written a list of professional codes of practice:
Being punctual: This is a tough one because though sometimes transport, the weather, the world are against you being on time it's something that I believe can really make a difference. If you turn up early you reflect the image of someone who's organized and prepared. At auditions everyones always on a tight schedule with room bookings, the pianist and you don't want to be the one to mess up all the planning!
Looking neat and suitable: When going to auditions at the very least they want to see somebody who's made an effort. In this industry it's had enough to get seen in an audition, so they want to see that you care and want the job, not somebody who just rolled out of bed. I also think you should give a hint of the role. You're making their job easier by showing how you fit with the production and also showing that you've put some thought into it.
Being respectful of instructions being given: It's hard to do things when you don't fully understand the reason or agree, but in auditions I believe you just have to suck it up. So they want you to do it facing the back. Just do it!!
To be prepared for anything they throw at you: So now they've decided that after seeing the jazz combination they now want pointe work. You don't want to be someone who gets caught out, being prepared for anything is never a bad thing.
To ALWAYS be polite: A wise person once said "You never know who'll get you your next job" Directors often ask the assistant, who shows you into the audition room, how the candidates behave away from the audition panel. It's important to show that you are somebody they want to worth with and employ in there company.