The cue sheet would list the title and author of a song, when to play it, roughly how long to play it for, and the publisher of the piece. Quite often, further notes were given of sound effects, tempo, and so on, so that every important factor of the film could be supervised. The musical director of a theater then went through the theater's music collection (generally listed by tempo) and picked out the appropriate cue. If he did not have that particular cue, he could replace it with another suitable piece, or order it through the company that created the cue sheet. A typical theater's music library could consist of a couple thousand to tens of thousands of pieces, depending on the budget of the theater.