For the original Final Fantasy, Sakaguchi required a larger production team than Square's previous titles. He began crafting the game's story while experimenting with gameplay ideas. Once the gameplay system and game world size was established, Sakaguchi integrated his story ideas into the available resources. A different approach has been taken for subsequent titles; the story is completed first and the game built around it. Designers have never been restricted by consistency, though most feel each title should have a minimum number of common elements. The development teams strive to create completely new worlds for each title, and avoid making new games too similar to previous ones. Game locations are conceptualized early in development and design details like building parts are fleshed out as a base for entire structures.
The first five games were directed by Sakaguchi, who also provided the original concepts. He served as a producer for subsequent games until he left Square in 2001. Yoshinori Kitase took over directing the games until Final Fantasy VIII, and has been followed by a new director for each new title. Hiroyuki Itō designed several gameplay systems, including Final Fantasy V's Job System, Final Fantasy VIII's Junction System and the Active Time Battle concept, which was used from Final Fantasy IV until Final Fantasy IX. Itō also co-directed Final Fantasy VI with Kitase. Kenji Terada was the scenario writer for the first four games; Kitase took over as scenario writer for Final Fantasy V through Final Fantasy VII. Kazushige Nojima became the series' primary scenario writer from Final Fantasy VII until his resignation in October 2003; he has since formed his own company, Stellavista. Nojima partially or completely wrote the stories for Final Fantasy VII, Final Fantasy VIII, Final Fantasy X, and Final Fantasy X-2. He also worked as the scenario writer for the spin off series, Kingdom Hearts.
Artistic design, including character and monster creations, was handled by Japanese artist Yoshitaka Amano from Final Fantasy through Final Fantasy VI. Amano also handled title logo designs for all of the main series and the image illustrations from Final Fantasy VII onward.Tetsuya Nomura was chosen to replace Amano because Nomura's designs were more adaptable to 3D graphics. He worked with the series from Final Fantasy VII through Final Fantasy X; for Final Fantasy IX, however, character designs were handled by Shukou Murase, Toshiyuki Itahana, and Shin Nagasawa.Nomura is also the character designer of the Kingdom Hearts series, Compilation of Final Fantasy VII, and the Fabula Nova Crystallis: Final Fantasy XIII. Other designers include Nobuyoshi Mihara and Akihiko Yoshida. Mihara was the character designer for Final Fantasy XI, and Yoshida served as character designer for Final Fantasy Tactics, the Square-produced Vagrant Story, and Final Fantasy XII.