Bastian's father is a dental technician who works in his home laboratory.
When Bastian was younger, his father would tell him stories and play with him, although he is described as becoming distant when his wife (Bastian's mother) dies unexpectedly and an "invisible wall" appears around him. He buys Bastian whatever he wants and spends time in his presence though rarely speaks to him, making Bastian feel neglected.
"[Bastian] couldn’t talk to his father anymore. There was an invisible wall around his father, and no one could get through to him. He never found fault and he never praised. Even when Bastian was put back in school, his father hadn't said anything. He had only looked at him in his sad, absent way, and Bastian felt that as far as his father was concerned he wasn’t there at all. That was how his father usually made him feel."
In the final chapter, when Bastian returns home, he gives his father the Water of Life, which cures him of his depression. He reconciles with Bastian and listens to his adventures in the Neverending Story.
In the first film, Barney is portrayed by Gerald McRaney.
In this film, Barney's name is not mentioned.
He is dismissive of Bastian's feelings, telling him that his mother's death can't get in the way of getting things done, and berates him for having his head in the clouds.
In the second film, Barney is played by John Wesley Shipp.
His occupation is changed from a dental technician to a technical sales engineer.
When Bastian is in The Neverending Story, Barney notices his disappearance. He finds the Neverending Story in Bastian's room and sees a sticker on the front cover that lists the address of Mr. Koreander's bookstore's. Barney rushes to the bookstore where Mr. Koreander tells him that he will find the answers inside the book. Returning later with a police officer, Barney is shocked to see the bookstore abandoned.
Eventually, Barney reads the book, where he follows Bastian's journey and is reunited with him at the end of the film.
In the third film, Barney is played by Kevin McNulty.
In this film, Barney appears to have no memory of reading the book. He marries a woman called Jane Baxter, who has a daughter: Nicole, thus creating some of the conflict within the story.
In the 2001 TV series, Barney's name is changed to Michael Bux, and he is played by Noel Burton.
His occupation is changed from a dental technician to a lawyer working for the law firm Caspar, Bux, Lalos, & Balaban.
Michael is revealed to have divorced Laura Mackenzie Bux one year prior to the events of the series.
After Laura's death in a car crash, Michael moves back into Laura's house, and starts a relationship with a realtor named April Jones, who is secretly a Fantasian in disguise, sent by Xayide the Dark Princess to steal The Neverending Story, a magical book in the possession of Michael's son Bastian.
In one episode, G'mork, under the disguise of substitute teacher L.C. Blank, approaches Michael and hires him to be his lawyer. Mr. Blank had been "wrongfully dismissed" (Bastian and his friends erased him from the school computer), and he is suing Westmount Park School. After Mr. Blank threatens Bastian with his mom's broken "magic pencil", Bastian tells Michael about the letter he had received, and Michael, after comparing the letter to a list of grievances written by Mr. Blank, quits his post and threatens Mr. Blank with incarceration if he ever nears Bastian again.
- Bastian’s father is never given a name in the book nor the first film. He is given the name “Barney” for the second film and third film, and he is given the name "Michael" for the 2001 TV series.
- In the novel, Bastian's father is a dental technician; in the films, he is a technical sales engineer, and in the 2001 miniseries, he is a lawyer.