Full name: Rasd-Coduresa Diziet Embless Sma da' Marenhide
In State of the Art, Diziet Sma is on the ship GCU Arbitrary. The mission is to assess Earth for contact by the Culture. Diziet is in favour of contact between the Culture and Earth, which she thinks will halt Earth's many conflicts and improve their quality of life. The GCU decides against this.
In Use of Weapons, Diziet recruits a person called Cheradenine Zakalwe, a non-Culture citizen, to help with aiding less advanced races with military problems to advance the Culture's goals.