This chapter discusses working with other actors. It explains that while actors work individually on their roles, true performances involve coordination with others. Any performance can be divided into actions and reactions, which influence each other. Actors must react genuinely to their partners and coordinate their actions to achieve the same goals. Physical contact on stage, like fights or kisses, require rehearsal to create the illusion of contact through reactions rather than actual contact. Illusions are most convincing when audiences are distracted from the point of action. Extensive rehearsal is needed to coordinate illusions between actors.