Because of this she is often perceived as uncannily observant. Along with compiling script notes, keeping an eye on the edit and supervising continuity, the script supervisor is the one person on set devoted to watching the words. During shooting she has the most accurate, up to the minute script because she incorporates all rewrites and revisions into and pulls all deletions out of her script copy. She makes sure story information is consistent, details mentioned match details seen, dialogue has overall logic and that the actors follow the written script. To do this the script supervisor works closely with the director and actors.
Actors vary as much as directors.
She is available to run lines with actors between takes, to read off-camera dialogue, and to write down ad libs and changes in dialogue so they can be matched in reverse shots and additional coverage. The script supervisor also helps the actors match themselves from shot to shot. As with all the film crafts, script supervision demands a personality suited to the work. Being observant, quiet, organized, a little on the obsessive side, able to assert yourself when needed, will all serve a script supervisor well. Several options are available to learn the craft.