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.
Kate Jackson was the original choice for the part of Joanna Kramer; her commitment to "Charlie's Angels" (1976) prevented her from taking the role.
Dustin Hoffman offered the part of Ted's one-night-stand to Joan Lunden, after seeing her on WABC Eyewitness News (she was an on-air reporter at the time). Upon learning that the role required some nudity Lunden turned the part down.
Dustin Hoffman, having just lived through divorce himself, contributed many personal moments and dialogue to the film and was offered shared screenplay credit by director Robert Benton, but turned it down.
Meryl Streep wrote her own courtroom speech upon writer-director Robert Benton's suggestion, after she told him she wasn't satisfied with the way it was originally written.
Dustin Hoffman worked extensively with Justin Henry on each scene, discussing them at length to put him at ease.
The set for the apartment was designed to fit exactly within the size of the apartments in the building used for exteriors.
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 first cut ran 43 minutes longer than the eventual film, and included additional scenes with Jane Alexander, JoBeth Williams, and an eliminated character of a housekeeper.
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.
The music played during the opening credits is Antonio Vivaldi's Mandolin Concerto.
The woman that Hoffman suddenly kisses at the party is Ingeborg Sørensen, a former Miss Norway and Playboy Playmate.
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 on location in New York City at JG Melon's on 74th and 3rd. There is now a framed still from the film on the wall next to the table where the scene was shot.
JoBeth Williams's funny nude scene was optically darkened for the film's theatrical run in order to avoid an R rating. However, the undarkened version very often turns up on some television prints.
Dustin Hoffman devised 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 because he wanted to make sure that it got in the shot. Streep's shocked reaction is real, but she managed to stay 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.
James Caan was offered the role of Ted Kramer but turned it down.
When Justin Henry's character Billy cries, it is genuine. The director asked Justin to think of a saddening memory before the take.
At the end of the very last scene, Meryl Streep, speaking as herself, believing that the scene had ended, asked Dustin Hoffman if her eye make-up was messed up from crying. The director kept it in the movie.
[June 2008] Ranked #3 on the American Film Institute's list of the 10 greatest films in the genre "Courtroom Drama".