The details of what a Studio Art Director (SAD) does vary from studio to studio.  This role becomes beneficial and arguably necessary as a studio begins to grow to handle more than one project simultaneously.

I filled this role at Volition, Inc. from 2002 – 2010.  For my experience, it had a multitude of responsibilities and a high degree of variance of what one day is like compared to the next.  I have illustrated these high level responsibilities below, broken in to two separate roles which I recommended and help implement at Volition a few years ago.  To be clear, prior to the split, all of the items fell under the single Studio Art Director job description.  At this time, the Studio Artist Manager reports in to the Studio Art Director.