I am currently in the process of re-doing my master bathroom. I will be re-tiling the wall and also adding a new shower fixture. Is it better to re-tile first and then add the new fixture or the other way around. Or does it really matter?

Thanks!

I'd add it last, then you won't have to work around it.

What do you mean 'shower fixture'?

If you mean faucet, spout or shower head, then do the rough-in plumbing first, then install cement board, then tile, then install the finish plumbing pieces.

Same for lights/ fans. First do rough-in then cement board then tile then install the finish electrical piece.

If you mean glass walls/ doors, then it is best to ensure you have enough support behind the wall that you'll be able to screw in to... then cement board, then tile, then install the walls/ doors.