Koji Steven Sakai has written two feature films Haunted Highway (2006) and The People I've Slept With (2009), the latter of which he also produced.

Koji is a graduate from the University of Southern California's Masters of Professional Writing program. He studied under teachers such as Syd Field, Oscar nominated writer/producer/director Mel Shavelson, and iconic novelist Hubert Selby Jr.

He has held several fellowships, starting with the most recent, which include: The Writers Boot Camp Fellowship (2009), The Producers Guild: Power of Diversity Workshop (2009), Film Independent's Project: Involve (2007), Visual Communication's Armed with a Camera (2006), and Screenwriting Expo 4: New Visions Fellowship award (2005).

Koji's first film, Haunted Highway, was directed by Junichi Suzuki and distributed by Lions Gate DVD. He co-wrote it with Naoko Ihara Witmer and the director.  Koji also wrote and produced The People I Slept With, a feature romantic comedy directed by Quentin Lee and staring Karin Anna Cheung, Wilson Cruz, Archie Kao, and James Shigeta. The People I Slept With premiered in the fall of 2009 and has played at prestigious festivals such as Los Angeles' Fusion Outfest Film Festival, Sao Paulo International Film Festival, and the Golden Horse Film Festival in Taiwan. The film enjoyed a short theatrical run and played on MTV's Logo TV and released on DVD by Maya Entertainment in 2011.

Koji has taught screenwriting classes for Asian American Poetry & Writers organization, and currently teaches for Visual Communications and Pasadena City College – Extended Learning.

In addition to his work in film, Koji is a regular contributor to 8Asians, a blog dedicated to Asian American culture, history, and news. 8Asians averages about 150 thousand hits a month. He also writes for Discover Nikkei, a community website about Nikkei identity, history and experiences. Finally, he contributed a story (Meet Joe) to Secret Identities: The Asian American Superhero Anthology, the first graphic novel anthology written/drawn/and about Asian Americans. Secret Identities was released by New Press in 2009.

Koji is also the manager of public programs at the Japanese American National Museum. He is in charge of the concerts, lectures, workshops, family days, screenings, and other public events. While at the National Museum, Koji and his producing partner Quentin Lee founded and continue to program the ID Film Festival, which showcases films by Asian Pacific Islander filmmakers for API filmmakers.