The opening title sequence, directed by Saul Bass, were created using stop motion and dragging around strips of colored paper.
Some people have claimed that there was a body double for parts of the shower scene, but this has also been disputed. The only time it isn't Leigh is during a few of the shots of Norman carrying her dead body, Hitchcock said.
It's rumored that a nipple can be seen during the shower scene. However, Janet Leigh says she was wearing what were essentially skin-colored pasties over her privates. Try as they might, there couldn't have been nudity while she was wearing those.
There is some controversy over who actually directed the shower scene. Saul Bass, who did the title sequence and storyboards, claimed to have been the director, but this was met with denials from Hitchcock himself, Janet Leigh, and the cinematographer, John Russell.
The opening scene of the film takes place in the Westward Ho, a famous hotel in downtown Phoenix, AZ.
Hitchcock wanted to make a low-budget black-and-white movie partly because he wanted to save money but more as a test. Most cheaply made horror films of the time were terrible but still did well at the box office. Hitchcock wanted to see what would happen if a good black-and-white horror film were made. All of his subsequent films were shot in color.
Hitchcock makes a cameo wearing a cowboy hat outside of the Real Estate office as Marion Crane enters approx. 7 min. into the film.
Alfred Hitchcock bought the rights to the novel anonymously from Robert Bloch for only US$9,000. He then bought up as many copies of the novel as he could to keep the ending a secret.
In the infamous shower scene, the filmmakers used chocolate sauce to stand in for blood.
This movie marks the first time a toilet was shown flushing onscreen.
Alfred Hitchcock tested the fear factor of Mother's corpse by placing it in Janet Leigh's dressing room and listening to how loud she screamed when she discovered it there.