Up and coming New York advertising executive Ted Kramer believes that his role and responsibility to his family is to be the household breadwinner, which means a focus on career. Joanna Kramer, his wife of eight years, is relegated to role of housewife and mother to their five and a half year old son, Billy Kramer, as Ted doesn't want her to work outside the house. As such, Joanna, on the encouragement of Margaret Phelps, a recent divorcee in their apartment building and one of Joanna's primary confidantes, decides to abandon the marriage, and leave Billy with Ted, as she feels she can't properly take care of Billy in her current fragile mental state. Ted believes that Joanna is solely going through a phase, and that she will return home in a day or two, which she doesn't. So, Ted has to make some major adjustments in his life. Beyond the time of fitting in Joanna's duties into his work schedule, Ted is ill equipped to take care of the household chores and be Billy's sole caregiver, which is made more difficult as Billy has his own ill feelings about the entire situation. Ted and Billy go through a difficult period in learning how to deal with each other as father and son, but the relationship eventually blossoms into a truly loving one, with Margaret being one of their biggest supporters. Two issues threaten Ted and Billy's new-found familial happiness: the negative effect his new time priority with Billy has on maintaining a productive work life, and the arrival fifteen months later of a newly confidant Joanna, who wants custody of her son.