Sylvia: West (Karoki, Kay, Carlyle)
Carroll Baker
Alan Macklin
George Maharis
Father Gonzales
Jay Novello
Big Shirley
Nancy Kovack
Gavin Cullen
Gene Lyons
Wilbur (aka "Muscles")
Anthony Caruso
Gus
Alan Carney
Mrs. Karoki
Shirley O'Hara
Herbert, the Boy in the Library (uncredited)
Ricky Allen
Pudgey Smith (uncredited)
Val Avery
Anne (uncredited)
Majel Barrett
Maitre'd (uncredited)
Jean Del Val
Jane (Bronson) Phillips
Joanne Dru
Molly Banter (uncredited)
Connie Gilchrist
Butler (uncredited)
Gavin Gordon
Calligraphy Professor (uncredited)
Clive Halliday
Sid (uncredited)
John Harmon
Mr. Leland (uncredited)
Stacy Harris
Assistant Principal (uncredited)
Kathleen Mulqueen
Pancho Guzman (uncredited)
Manuel Padilla Jr.
(uncredited)
Robert Random
Professor Eglebert (uncredited)
Gene Roth
Clerk at Private Hospital (uncredited)
Geraldine Wall
Frederic Summers
Peter Lawford
Peter Memel (uncredited)
Paul Wexler
Irma Olanski
Viveca Lindfors
Oscar Stewart
Edmond O'Brien
Jonas Karoki
Aldo Ray
Mrs. Argona / Grace Argona
Ann Sothern
Bruce Stamford III
Lloyd Bochner
Lola Diamond
Paul Gilbert
Makeup Supervisor
Wally Westmore
Director
Gordon Douglas
Screenplay
Howard Fast
Costume Design
Edith Head
Set Decoration
Sam Comer
Theme Song Performance
Paul Anka
Music
David Raksin
Sydney Boehm
Other
Joan Joseff
Editor
Frank Bracht
Special Effects
Paul K. Lerpae
Orchestrator
Edward B. Powell
Art Direction
Roland Anderson
Sound Recordist
John Wilkinson
Associate Producer
Shirley Mellner
Harry Lindgren
Van Cleave
Visual Effects
Farciot Edouart
Sound Editor
Howard Beals
Producer
Martin Poll
Arthur Krams
Steve Shagan
Assistant Director
Dick Moder
Hal Pereira
Cinematography
Joseph Ruttenberg
Hair Supervisor
Nellie Manley