Henry Mancini said that although the scoring was the most difficult in his career, the music he composed for this movie was always his favorite.
Several biographies of Audrey Hepburn state she was very nervous shooting her first nude scenes for this film, particularly a skinny dipping sequence. If such a scene was shot, it didn't end up in the final print.
Audrey Hepburn does not wear her trademark designer clothes by Givenchy in this film. Director Stanley Donen insisted that it was essential for her character that she wear clothes that could be bought in a store.
Is one of the very few films in which Audrey Hepburn uses profanity. She says "damn" and "bastard" over the course of the film.
Jacqueline Bisset is partially dubbed by another actress. Soon after filming, Bisset received a role in a major Hollywood film. She left England and was therefore unavailable when it came time to re-dub some of her lines.