Walter Matthau as Paul Manning

Inger Stevens as Ruth Manning

Sue Ane Langdon as Irma Johnson

Jackie Russell as Jackie Russell

Robert Morse as Ed Stander

Aline Towne as Mousey Man's Wife

Claire Kelly as Harriet Stander

Eve Brent as Joe X's Blowsy Blonde

Marvin Brody as Taxi Driver

Majel Barrett as Mrs. Fred V.

Marian Mason as Mrs. Rance G.

Tommy Farrell as Rance G.'s Hanger On

Linda Harrison as Miss Stardust

Jason Wingreen as Harry 'Big Fella' Johnson

Pat Becker as Party Guest

Fred Holliday as Party Guest

Robert Patten as Party Guest

Ray Montgomery as Party Guest

Virginia Wood as Bubbles

Lucille Ball as Technical Adviser (Mrs. Joe X)

Jack Benny as Technical Adviser (Ollie 'Sweet Lips')

Polly Bergen as Technical Adviser (Clara Brown)

Joey Bishop as Technical Adviser (Charlie)

Sid Caesar as Technical Adviser (at Romanoff's)

Art Carney as Technical Adviser (Joe X)

Wally Cox as Technical Adviser (Married 14 years)

Hal March as Technical Adviser (Man who loses coat)

Louis Nye as Technical Adviser (Irving, House Buyer)

Carl Reiner as Technical Adviser (Rance G.)

Phil Silvers as Technical Advisor (Realtor)

Terry-Thomas as Technical Adviser (Harold aka Tiger)

Ben Blue as Technical Adviser (Shoeless)

Ann Morgan Guilbert as Technical Adviser (Charlie's Wife)

Jeffrey Hunter as Technical Adviser (Mountain Climber)

Marty Ingels as Technical Adviser (Meat Eater)

Sam Jaffe as Technical Adviser (Shrink)

Jayne Mansfield as Technical Adviser (Girl with Harold)

Sanita Pelkey as Girl in Introduction (uncredited)

Delores Wells as Very Attractive Woman (uncredited)

Joy Harmon as Party Girl in Bar (uncredited)

Dee Carroll as Party Guest

Jackie Joseph as Janet Brophy

Heather Young as Girl with Megaphone

Evelyn King as Female Plaintiff

Nancy DeCarl as Woman with Baby

Warrene Ott as Woman with Gun

Michael Romanoff as Romanoff's Maitre D'

Karen Arthur as Lady Dinner Partner at Romanoff's

Damian London as Lone Male Diner at Romanoff's

Chanin Hale as Miss Crenshaw

Julie Tate as Woman in Bed at Motel

George N. Neise as Man in Bed at Motel

Tim Herbert as Shoe Clerk

Patricia Sides as Mau Mau Dancer at Bantu Cusine

Pat McCaffrie as Happy Hour Motel Clerk

Jimmy Cross as Mr. Brown

Elaine Devry as Jocelyn Montgomery