William Wyler thought the characterization of Mrs. Dodsworth was too black and white and insisted on some subtleties to the performance. Ruth Chatterton vigorously disagreed with this interpretation and the two would often argue fiercely on the subject. At one point Chatterton slapped Wyler across the face and retreated to her dressing room. In her memoirs, Mary Astor observed that Chatterton's character "was that of a woman trying to hang onto her youth--which was exactly what Ruth herself was doing. It touched a nerve."
Mary Astor wrote in her memoirs that Edith Cortright was her favorite role, also reflecting that she channeled her struggle of her public divorce into her role: "When I went into court and faced the bedlam . . . that would have broken me up completely, I kept the little pot boiling that was Edith Cortright."
At the time of filming, Mary Astor was going through a very public and very scandalous divorce from her husband, who used Astor's diary to prove that she had been having an affair with playwright George S. Kaufman. With the press constantly stalking her, she sometimes slept on the set to avoid confrontation. Many people involved in the production sided with Astor throughout the ordeal, including William Wyler, Samuel Goldwyn and Ruth Chatterton, who appeared as a character witness on Astor's behalf.
William Wyler spent a whole afternoon shooting the sequence where Fran (Ruth Chatterton) burns a letter from her husband; he wanted the letter to specifically blow gently along the terrace, stop for a moment, and then continue to flutter as the scene faded to black as a metaphor for Fran and Sam's failing marriage.
Mary Astor enjoyed working with William Wyler, finding him to be "an inspirational director, tough and exacting but sensitive." She especially appreciated how he ended the film on a close-up of her, not strictly out of vanity but from the awareness that the audience would enjoy having the story end on the high note of Edith's radiance at seeing Sam return to her.
William Wyler and Ruth Chatterton fought bitterly almost daily on the interpretation of Fran. Chatterton felt she should be played entirely as a villainess, whereas Wyler found reasons to sympathize with the character. According to Mary Astor, the tension was increased by Chatterton's own desperation at her advancing age. At 43 she was far from an old woman but well past the age when actresses typically enjoyed continued audience appeal and their choice of roles. Once a big star on stage, and briefly one in films a few years earlier, her success was waning and, according to Wyler, she exhibited very "haughty" behavior on the set. She was self-conscious about her figure and her looks, insisting on daily facials to maintain a youthful glow. Her insecurities manifested themselves as hatred and fear toward Wyler and his multiple-take working method. At one point she reportedly slapped the director's face and locked herself in her dressing room.
Although the film was shot entirely in the studio, William Wyler sent a camera crew to London, Paris, Vienna, Montreux and Naples for background shots that would be projected behind the sets to recreate the Dodsworths' European tour. Wyler knew many of the locales from personal travels and gave minutely detailed instructions about the kinds of shots he wanted, but many of them were rejected in the final cut in order to keep the film from feeling like a travelogue. Only those crucial to the story survived.
David Niven later said he was "bloody miserable" working with William Wyler, whom he described as a "Jekyll and Hyde" and "a sonofabitch to work with." Although conceding Wyler could be "kind, fun and cozy" off the set, Niven said "he became a fiend the moment his bottom touched down in his director's chair." Wyler was not terribly impressed with Niven's talent, either, later noting that he was little more than "a sort of playboy around town." However, the director thought that since Niven was essentially playing himself on screen, he was perfect for the part of the charming cad Captain Lockert.
William Wyler and Walter Huston were friends who worked well together, especially since their ideas about screen acting perfectly meshed. "No acting ruses, no acting devices, just the convincing power that comes from complete understanding of a role," Wyler noted. He credited Huston's thousands of hours on stage in the role with making for a "letter-perfect" film performance.