This was Elvis Presley's final dramatic film before his death on August 16, 1977 at the age of 42.

Director William A. Graham said in an interview years after the making of this film that Elvis Presley was the nicest man he had ever met.

When Elvis is playing the piano and Mary Tyler Moore the guitar, the tune they're playing together is "Lawdy Miss Clawdy", a song that Elvis first recorded in 1956. It is the only recorded performance of this song that features Elvis on the piano.

One of the songs in this film, "Rubberneckin'," wasn't originally recorded for this film, but was recorded at Elvis's classic Memphis recording sessions in 1969 and is the B side to his million seller, "Don't Cry Daddy".

Mary Tyler Moore and Edward Asner would soon become co-stars of her self-named The Mary Tyler Moore Show (1970) Show. In Change of Habit, however, they shared no scenes together.

This movie was a part of contract made between Elvis Presley and NBC in 1968 which included the "Elvis Presley's '68 Comeback Special" (1968) (TV) and this movie.

Elvis was visited on set by the gospel singer, Mahalia Jackson.

Elvis was paid a salary of $850,000 plus 50% of the profits to make this film as part of a deal with NBC that included his 1968 television special.

In a 1995 interview on the Terry Gross radio show, "Fresh Air", Mary Tyler Moore stated she was Elvis' last leading lady. She added that Elvis was quoted as saying there was only one leading lady he did not sleep with. Moore implied to Terry Gross that she was that one leading lady.

Elvis used his character`s name in Change of Habit, John Carpenter, as a pseudonym when travelling in the 1970s. He also used the name John Burroughs.

The song Rubberneckin wasn't recorded for this film. It was recorded during Elvis` famed sessions at American Sound Studios and chosen for inclusion in the opening scene.

This was Mary Tyler Moore's last film until Ordinary People (1980) 11 years later.

Elvis Presley plays a character by the name of John Carpenter. Oddly enough, director John Carpenter of Halloween fame would later go on to direct a two-part miniseries about Elvis in 1979

This was Richard Carlson's final film before his death on November 24, 1977 at the age of 65.

Spent four weeks on the Variety Box Office Survey, peaking at #17.

This film was produced by NBC and distributed by Universal, some 35 years prior to the two firms merging.

This never received a cinema release in the UK. It was premiered instead on BBC One on August 24th, 1971.

Only feature film starring Elvis Presley which wasn't released theatrically in Finland.

The first film in the West to mention autism.

Director William A. Graham told in an interview in early 2000 that he thought Sister Michelle Gallagher would choose Dr. John Carpenter instead of being nun at the end of the film.