A script assistant is more precisely an assistant script supervisor, working with the script supervisor in maintaining records and processing script changes during principal photography. Unlike the supervisor, the script assistant does not supervise any actual filming.
As of 2016[update], only Ross Southard has been credited as a script assistant on a DWU production. While only officially credited on one episode of Torchwood (that is, Adrift), Helen Raynor confirmed in PCOM: The Sontaran Stratagem that Ross was working under the same title at the time in the Doctor Who office, as well.