A Number is a 2002 play by English playwright Caryl Churchill which addresses the subject of human cloning and identity. The story, set in the near future, is structured around the conflict between a father and his "sons". The father, named Salter, suffered the death of his wife and children, and arranged to clone a new child from the one he "lost". Thirty years later, three of those "sons" (Bernard one and two and Michael Black) encounter Salter.
In 2004, the play made its American debut at the New York Theatre Workshop in a production starring Sam Shepard (later Arliss Howard) and Dallas Roberts.