 | Cary Grant als Peter Joshua |
 | Audrey Hepburn als Regina Lampert |
 | Walter Matthau als Hamilton Bartholemew |
 | James Coburn als Tex Panthollow |
 | George Kennedy als Herman Scobie |
 | Dominique Minot als Sylvie Gaudel |
 | Ned Glass als Leopold Gideon |
 | Jacques Marin als Edouard Grandpierre |
 | Paul Bonifas als Mr. Felix |
 | Thomas Chelimsky als Jean-Louis Gaudel |
 | Marc Arian als Subway Passenger (uncredited) |
| Claudine Berg als Maid (uncredited) |
 | Marcel Bernier als Taxi Driver (uncredited) |
| Albert Daumergue als Man in Stamp Market (uncredited) |
 | Raoul Delfosse als Taxi Driver (uncredited) |
 | Stanley Donen als Man in Elevator (voice) (uncredited) |
| Jean Gold als Writer On Cafe Terrace (uncredited) |
 | Chantal Goya als (uncredited) |
 | Clément Harari als German Tourist (uncredited) |
 | Monte Landis als Master of Ceremonies at Club (uncredited) |
 | Bernard Musson als Hotel Receptionnist (uncredited) |
| Antonio Passalia als Italian Representative at URESCO (uncredited) |
 | Jacques Préboist als Ice Cream Salesman (uncredited) |
 | Peter Stone als Man in Elevator / Marine (voice) (uncredited) |
 | Michel Thomass als Embassy Driver (uncredited) |
 | Roger Trapp als Mortuary Employee (uncredited) |
| Louis Viret als Hallmark Employee On Subway (uncredited) |
| Peter Stone | Screenplay |
| Peter Stone | Story |
| Stanley Donen | Director |
| Marc Maurette | Second Unit |
| Henry Mancini | Original Music Composer |
| Jim Clark | Editor |
| Jean-André d'Eaubonne | Art Direction |
| Stanley Donen | Producer |
| Charles Lang | Director of Photography |
| Marc Behm | Story |
| Hubert de Givenchy | Costume Design |
| Marc Maurette | Assistant Director |
| Bob Jones | Sound Mixer |
| Allan Morrison | Sound Editor |
| Garth Inns | Special Effects |
| Jacques Carrère | Sound Mixer |
| John O'Gorman | Makeup Artist |
| Henri Tiquet | Camera Operator |
| Douglas Gamley | Orchestrator |
| Henri Persin | Second Unit Cinematographer |
| Vincent Rossell | Still Photographer |
| Alberto De Rossi | Makeup Artist |
| Paul Stader | Stunts |
| Edward Muhl | Executive In Charge Of Production |
| Auguste Capelier | Assistant Art Director |
| Maurice Binder | Title Designer |
| Robert Ellis | Animation |
| James H. Ware | Associate Producer |
| Léopold Schlosberg | Production Manager |
| Arthur Carroll | Production Director |
| Johnny Mercer | Songs |
| Henry Mancini | Songs |
