Animators have the responsibility of performance of the characters. They must not only be the actor, but in many ways, the director as well. The detail of how a character enters a room, what props they are carrying, where have they come from, where are they going. These topics are all covered in the Nina Foch Course. Lee Unkrich, who directed Toy Story 3 was one of Nina Foch's students and learned these basics from her class.