* Julia Stiles as Nicky Parsons
* Joan Allen as Pamela Landy
* Chris Cooper as Alexander Conklin
* Brian Cox as Ward Abbott
* Scott Glenn as Ezra Kramer
* David Strathairn as "The Professor" (credited as "Dr. Albert Hirsch")
* Olek Krupa as Jarda
While Damon and Stiles were the only actors to appear in all four Bourne films, some of the others, like Joan Allen, appeared in other Bourne films as well.