In episode 1, when Joker debriefs Yomiko on the I-Jin incident, a screen displays a list of people who were candidates for the I-Jin project. One of the names is series creator Hideyuki Kurata.
Before creator Hideyuki Kurata even began writing the light novels and manga, he has stated in the staff interview published in R.O.D the Official Archive art book that in 1998, SME Visual Works (the company is now known as Sony Music) approached Kurata to pitch a female spy anime. Kurata has always had a deep love for literature and the action genre. While reading the manga series Ushio and Tora, he drew inspiration from the way the manga's action sequences seamlessly unfold with the story and decided to combine this style of action that was also "rife with literary references" in his pitch deck. He drew further inspiration from his friend's canceled anime project (which was spy-themed). His friend, Yosuke Kuroda (an anime scriptwriter) encouraged Kurata, telling him he always wanted to create "a John Woo thing, but with a female" and contributed ideas to the characters' designs in the early stages. Taraku Uon was eventually brought on as the series' original character designer (Masashi Ishihama would later adjust the designs for the anime as chief animation director), though Uon used Kuroda's early doodles of Yomiko to finalize her design (her signature parted bangs, long coat and large bag were Kuroda's inventions).
The acronym R.O.D stands for 'Read or Die'.