The famous ice-cream scene, where Billy challenges his father by skipping dinner and going straight for dessert, was completely improvised by both Dustin Hoffman and Justin Henry. Director Robert Benton liked the scene so much that he decided to keep it in the film.
Dustin Hoffman planned the moment when he throws his wine glass against the wall during the restaurant scene with Meryl Streep. The only person he warned in advance was the cameraman, to make sure that it got in the shot. Streep's shocked reaction is real, but she stayed in character long enough for the director to yell cut. In the documentary on the DVD, she recalls yelling at Hoffman as soon as the shot was over for scaring her so badly.
The strength of the performances of the two lead actors can be at least partly attributed to what was going on in their private lives at the time. Dustin Hoffman was in the midst of a messy divorce, while Meryl Streep was still recovering from the death of her lover, John Cazale.
Dustin Hoffman, who was going through a marital separation and who divorced his first wife soon after filming ended, contributed many personal moments and dialogue. Director Robert Benton, offered shared screenplay credit, but Hoffman turned it down.
When Justin Henry was Oscar nominated for the Best Supporting Actor Academy Award, Henry at age 8 became the youngest ever person to be nominated for this award as well as the youngest ever Oscar nominee in any category, a record which still stands today [August 2012].
Meryl Streep was originally cast in the role of Ted's one-night-stand, eventually played by JoBeth Williams. When Kate Jackson was contractually unable to accept the role of Joanna, it was offered to Streep.
The scene between Dustin Hoffman and Meryl Streep in the restaurant was filmed at JG Melon's, on 74th and 3rd in Manhattan. A framed still from the film hangs on the wall next to the table where the scene was shot.
Dustin Hoffman and Meryl Streep would often, jokingly, try to get Justin Henry to pick one of them over the other. One day on the set, Hoffman asked Henry who he'd rather be with. Henry said, "Her. She's nicer," to which Hoffman replied, "Oh yeah? Work with her five weeks then see what you say."
Meryl Streep requested changes to her character, as she felt that the story was relying on the audience to understand why Joanna left without letting Joanna express it for herself. It was her belief that the character as written, in both the screenplay and the book, was too one-dimensional, an obvious villain for Ted and Billy to react to and change their lives accordingly.
There was initially tension between Dustin Hoffman and Meryl Streep. Hoffman was hearing lots of advance publicity about newcomer Streep and how she was mastering the role and Hoffman felt he was being upstaged. When Streep wanted to change around the dialogue in the restaurant meeting scene, Hoffman became furious. As Hoffman recalled, "I hated her guts. Yes, I hated her guts. But I respected her." He accepted that Streep wasn't arguing for what was best for her character but what was best for the movie.
Dustin Hoffman offered the part of Ted's one-night-stand to Joan Lunden, who was a news reporter at the time, after seeing her on WABC Eyewitness News. Lunden turned the part down when she learned that the role required some nudity.
First of two back-to-back consecutive movies to win the Academy Award for Best Picture that was a contemporary film drama about interpersonal relationships and family bonds. The next year's winner was Ordinary People (1980).
Billy's crying is real. The director asked Justin Henry to think of a saddening memory before the take. Reportedly, at the Golden Globe Awards in 1980, when Ricky Schroder won the Best New Male Star of the Year award, according to the book 'The Academy Awards: The Complete Unofficial History', Henry "threw a raging tantrum".
Robert Benton advised cinematographer Néstor Almendros to base the look and color of the film on the paintings of Piero della Francesca. Almendros also used the work of David Hockney as an inspiration, and designed a realistic look, using source lighting in rooms with ceilings and available light in exteriors.
The final courtroom scene had one important rewrite: Joanna's explanation of why she left. Robert Benton feared major delays but, in fact, Meryl Streep had in mind what she wanted and quickly rewrote the monologue. Benton said, "Well, the scene is brilliant. I cut only two lines. What you see there is hers."
Kate Jackson was the original choice for Joanna Kramer. She had to decline due to her commitment to Charlie's Angels (1976), although an alternative reason has also been reported. According to the book "The Academy Awards: The Complete Unofficial History", Sherry Lansing of the Columbia Pictures studio "insisted on her [Streep] over Kate Jackson".
When Néstor Almendros found out they were planning on decorating Billy's room with Disney figures, he objected. Not because of anything having to do with lighting and camerawork, rather, he felt it would be intrusive. He said, "I thought that would be like inviting a third character into the intimate scenes between the child and mother and father." He suggested painting clouds on the walls instead. Robert Benton liked and approved the idea.
In the famous "fight scene", where Ted and Billy fight over the ice cream, the flavour is "chocolate-chocolate-chip". This is the exact same flavour that Dustin Hoffman, brings to his date with Teri Garr, in Tootsie (1982).
The book Ted is shown reading to Billy after the scene where he spots Joanna watching them is an English translation of "Le Trésor de Rackham le Rouge" ("Red Rackham's Treasure") from "Les Adventures de Tintin" ("The Adventures of Tintin") comic series by Hergé.