As Choreographer, your central role is to stage the movement pieces of the show. This can range from big musical numbers, to fight choreo, to physical theatre and scene transitions. You must plan the movements and formations, then teach them and ensure they are properly understood.
This role requires working closely with every other member of the cast and crew. It is important to speak with the Director, both before choreographing and after you've initially staged a number, to ensure that you are working with their vision for the show. Different directors will want to be involved in the staging of numbers to different extents, so you need to be prepared to fit to their style. Similarly, the abilities of performers will vary dramatically, so you need to be able to listen to your cast and ensure that they are comfortable with the movements. Finally, you need to coordinate with the Costume, Lighting and Set Designers, to ensure that all movements will be possible for performers (the restrictions imposed by costumes are easily underestimated).