Son was born in Philadelphia, Pennsylvania and raised in Dover, Delaware. Son said that it was a very small town with very few Asian-Americans. Son has an older brother, Grant Son.
Son's father, Yong Sup Son, and mother, Soon Chum "Ruby" Son, were both from Korea. Son's mother came to the United States in 1963. She had six sisters in Korea. Son said her parents met in Philadelphia, where her father was a student at the College of Pharmacy and her mother was an exchange nurse at Lankenau Hospital. They moved to Dover in 1967, where they owned and operated the Town Drug Store in the Milford Shopping Center in Milford, Delaware. Son said she grew up working in the drug store.
Son said that she knew she wanted to be a writer when she was 9 years old. Son credits seeing Joseph Papp's production of Hamlet at the Joseph Papp Public Theater / New York Shakespeare Festival on a 1983 high school senior class trip for her inspiration to be a playwright. Diane Venora starred in the lead role of Hamlet, the first woman to play the role. Hamlet was the first play she saw, and it was her first visit to a theater.
Son studied Dramatic Literature at New York University. When she was a senior in college she interned at La MaMa Experimental Theatre Club, an off-off Broadway theatre and cultural institution.
Son's first play was called Wrecked On Brecht and was published in 1987. For eight to 10 years, she wrote and produced short plays in the downtown area of Manhattan. Her play BOY premiered at La Jolla Playhouse in 1996 and was directed by Michael Greif. The storyline for BOY is based on Son's mother's family adopting a male cousin. It is a story in which a young girl's parents decide to raise her as a son. In 1998, her play Fishes premiered at New Georges in New York City. Son wrote the short play R.A.W. ('Cause I'm A Woman), which explores how men view Asian-American women.
Her first full-length play, Stop Kiss, debuted in 1998. It was critically acclaimed. The play was produced Off-Broadway in 1998 at The Public Theater in New York City. It was extended three times. The play's initial run featured Jessica Hecht, Saul Stein, Sandra Oh, Saundra McClain, Kevin Carroll, and Rick Holmes. Son met Oh—who has participated in readings of every play by Son since they met—in 1995 in Los Angeles while involved in the New Works Festival. The play features two women who kiss on the street, and are "grievously injured" in an attack. Themes include LGBT / gay bashing and identity.
After the first night's performance of Stop Kiss, Son realized she would no longer have to do "copyediting, proofreading, waitressing, and temping"—jobs she took to support herself before the play came out. It has since been produced by hundreds of theaters. In 2014, Stop Kiss was produced at the Pasadena Playhouse, where it made the Los Angeles Times' "Best of 2014" list.
In 2006, Son wrote Satellites, a play Sandra Oh starred in that was directed by Michael Grief at The Public Theater. Son said she wrote the part in Satellites with Oh in mind.
Son has worked in television since 2000, starting out as a story editor for The West Wing. She was Playwright in Residence at the Taper during this same time. She has also worked on Law & Order: Criminal Intent, Southland, and Blue Bloods (TV series).
In March 2015, Son began work on the ABC series American Crime. At the 2015 TCAs, NBC ordered the pilot for Love is a Four Letter Word. It will be produced by 20th Century Fox Television and Red Arrow’s US scripted arm, Fabrik Entertainment. Son will write and executive produce with Mikkel Bondesen and Kristen Campo.
Son has taught playwriting at Yale University and New York University. As of 2015, Son is the Playwrighting Program Chair of the Dramatists Guild of America's Fellows Program, a mentorship and support program for playwrights and musical theater writers. She is a member of the Dramatists Guild of America, Women in Theatre, and the Writers Guild of America, East. Son is an alumna of New Dramatists. Son said she has written much of her work (plays and television) at a non-profit urban writer's colony called The Writers Room in Greenwich Village.
Son lives in Brooklyn, New York, with her husband Michael Cosaboom and their three boys, the youngest of whom are twins. Son met Cosaboom, an Interactive Telecommunications Program major, when she worked at NYU in that department.
Son said her parents are very supportive of her writing career once "As long as you do something, do it well", she quotes them as saying.2017: 13 Reasons Why - Executive Producer; Co-Showrunner
2015: Love is a Four Letter Word – Executive Producer; Writer
2015: American Crime – Co-Executive Producer; Writer
2010–2014: Blue Bloods – Co-Executive Producer (13 episodes), Consulting Producer (10 episodes); Written by (4 episodes), Story (1 episode)
2013: Do No Harm – Consulting Producer (12 episodes); Written by (1 episode)
2013: Jo – Teleplay (2 episodes)
2012: NYC 22 – Co-Executive Producer (12 episodes); Written by (1 episode)
2010: Southland – Consulting Producer (6 episodes); Story (1 episode), Written by (1 episode)
2003–2008: Law & Order: Criminal Intent – Supervising Producer (23 episodes), Co-Executive Producer (22 episodes), Co-Producer (22 episodes), Producer (21 episodes); Teleplay (13 episodes), Story (12 episodes), Written by (1 episode); Executive Story Editor (17 episodes)
2000: The West Wing – Story Editor (2 episodes)
Won the Berilla Kerr award for playwriting
GLAAD Media Award for Best New York Production for Stop Kiss
Nominated for the John Gassner Playwriting prize
Recipient of an NEA/TCG Theatre Residency Grant with the Mark Taper Forum
Brooks Atkinson Fellowship at the Royal National Theatre in London
A member of the Playwrights Unit in Residence at the Joseph Papp Public Theater
Son, Diana. Wrecked On Brecht. 1987
Son, Diana. Stealing Fire. 1992
Son, Diana. 2000 Miles. 1993.
Son, Diana. R.A.W. ('Cause I'm a Woman) 1993.
Son, Diana. Happy Birthday Jack. Dixon, Michael Bigelow, and Amy Wegener. Humana Festival '99: The Complete Plays. Lyme, NH: Smith and Kraus, 1999. ISBN 978-1-575-25207-0
Son, Diana. The Moon Please. Lane, Eric, and Nina Shengold. Take Ten II: More Ten-Minute Plays. New York: Vintage, 2003. ISBN 978-1-400-03217-4
Son, Diana. BOY. Yew, Chay. Version 3.0: Contemporary Asian American Plays. New York: Theatre Communications Group, 2011. ISBN 978-1-559-36363-1
Son, Diana. R.A.W. ('Cause I'm A Woman). Perkins, Kathy A., and Roberta Uno. Contemporary Plays by Women of Color: An Anthology. London: Routledge, 1996. pp. 289–296. ISBN 978-0-415-11377-9
Son, Diana. Fishes. 1998.
Son, Diana. Siberia. 2003.
Son, Diana. The Moon Please. Great Short Plays: Volume 10. New York: Playscripts, 2013. pp. 63–74.
Son, Diana. Blind Date. 2011.
Son, Diana. Axis. Tricycle Theatre. The Bomb: A Partial History. London: Oberon Books, 2012. ISBN 978-1-849-43152-1
Son, Diana. Stop Kiss. Woodstock, NY: Overlook Press, 1999. ISBN 978-0-879-51737-3
Son, Diana. Satellites. New York: Dramatists Play Service, 2008. ISBN 978-0-822-22227-9
Son, Diana. I Will Follow. Hodges, Ben, and Paula Vogel. The Play That Changed My Life: America's Foremost Playwrights on the Plays That Influenced Them. New York: Applause Theatre & Cinema Books, 2009. pp. 136–141. ISBN 978-1-557-83740-0