"Psycho" was first scheduled to air on U.S. network TV in the fall of 1966. Just before it would have aired, however, Valerie Percy, the daughter of U.S. Senator Charles H. Percy (R-Illinois: 1967 - 85), was stabbed to death, apparently by an intruder, in a murder that, as of 2007, remains unsolved. It was deemed prudent, under the circumstances, to postpone the scheduled airing. Ultimately, the film was never shown on U.S. TV until 1970, following a highly successful theatrical re-release the previous year. At that time, Universal released in on the syndication market, where it quickly became a popular staple on local late night horror film showings.

Stuart Whitman was Hitchcock's first choice for the role of Sam Loomis.

Kim Stanley, noted Actors Studio legend, was offered the role of Lila, but turned it down due to personal reservations about working with Anthony Perkins.

Walt Disney refused to allow Alfred Hitchcock to film at Disneyland in the early 1960s because Hitchcock had made "that disgusting movie, 'Psycho'."

Alfred Hitchcock (and his cinematographer) may actually have put one over on the censors. If you watch the sequence of the hand clutching around the shower curtain, you will see the curtain on the left side of the frame, the hand comes in center frame and diverts you from what can just been seen out of focus in the background right of the frame. If you increase the contrast on your monitor (particularly effective by tilting the monitor of a portable DVD player) the background visual information clearly resolves itself into a pair of naked breasts. Janet Leigh claims that she was not nude during the filming of this scene and was actually wearing a moleskin suit for the shot where she falls forward over the side of the tub. This is not disputed, but there was a nude model used for overhead and insert shots; this would be the case for the breast shot in question. Leigh insisted to her death that no nude woman, herself or a stand-in, was used in the actual filming, but modern video technology, including frame-by-frame advance, reveals one, in profile so as to expose no "private parts" and with the top of the frame at shoulder level so as to prevent identification.

Alfred Hitchcock and Joseph Stefano originally conceived the film with a jazz score instead of Bernard Herrmann's miniature string orchestra.

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.

Alfred Hitchcock deferred his standard $250,000 salary in lieu of 60% of the film's net profits. His personal earnings from the film exceeded $15 million. Adjusted for inflation, that amount would now top $150 million in 2006 dollars.

Alfred Hitchcock even had a canvas chair with "Mrs. Bates" written on the back prominently placed and displayed on the set throughout shooting. This further added to the enigma surrounding who was the actress playing Mrs. Bates.

Alfred Hitchcock originally envisioned the shower sequence as completely silent, but Bernard Herrmann went ahead and scored it anyway, and upon hearing it, Hitchcock immediately changed his mind.

Alfred Hitchcock paid the title sequence designer Saul Bass (also credited as "Pictorial Consultant") $2,000 to draw storyboards for the scene where Arbogast is killed at the stairs. Bass was excited about the movie and asked Hitchcock for the opportunity. Hitchcock discarded his work because the shots showed Arbogast's feet slowly going up the stairs and this prepared the audience for a shock. Hitch wanted it to be a surprise and that's why he filmed Arbogast in a completely natural way.

Alfred Hitchcock produced this film when plans to make a film starring Audrey Hepburn, called "No Bail for the Judge," fell through.

Alfred Hitchcock ran a deliciously droll and terse radio ad in the summer of 1960. In an era when sponsors used "Brand X" to describe their competitors' products, Hitch's voice said he wanted to compare his new movie with "Brand X". Then, the sound of a horse neighing and horse clippity-clop sounds. Hitch's voice said simply "Brand X is a western." "Now for my picture", followed by a loud scream. End of commercial!

Alfred Hitchcock received several letters from ophthalmologists who noted that Janet Leigh's eyes were still contracted during the extreme closeups after her character's death. The pupils of a true corpse dilate after death. They told Hitchcock he could achieve a proper dead-eye effect by using belladonna drops. Hitchcock did so in all his later films.

Alfred Hitchcock strictly mandated, and even wrote into theater managers' contracts, that no one arriving after the start of each showing of "Psycho" would be admitted into the theater until the beginning of the next showing. Advertising artwork deceived audiences into thinking that Janet Leigh was its star, and patrons arriving after her murder would wonder where she was. Newspaper advertisements cleverly piqued audience curiosity with such statements as "You MUST see "Psycho" from the very beginning. No one - not even the President of the United States, not the theater manager's brother, not even the Queen of England (God bless her) - will be allowed into the theater after the beginning of each showing of "Psycho". This is to allow you to enjoy "Psycho" more. By the way, after you see the film, please do not give away the ending. It's the only one we have". News cameras photographed audience members waiting in lines outside theaters to see "Psycho", creating tremendous curiosity about the film and adding extra publicity.

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.

Alfred Hitchcock was so pleased with the score written by Bernard Herrmann that he doubled the composer's salary to $34,501. Hitchcock later said, "33% of the effect of Psycho was due to the music."

Alfred Hitchcock was very uneasy about the morphing of Norman's face into Mother's at the end of the film. He sent out three different versions of the film during its initial release. The first version included the ending seen on all prints today, the second contained no morphing at all, and the third contained the trick at the end, yet also included it at an earlier point in the film. When John Gavin as Sam Loomis comes back to the Bates Motel to look for Arbogast, there is a zooming shot of Norman standing by the swamp, looking very sinister. The third version of the film included the subtle morphing of Norman's face into Mother's at this moment.

Alfred Hitchcock: [bathroom] Marion hides in the bathroom to count the required number of bills.

Alfred Hitchcock: [hair] Lila, and Mother.