Scott David Westerfeld is an American writer of young adult fiction, best known for his Uglies and Leviathan series. Born on May 5, 1963, Westerfeld has authored over thirty novels, five of which are intended for adults and the remaining twenty-five for young adults.

Westerfeld's most renowned work, the Uglies series, explores a future where cosmetic surgery is compulsory at sixteen. He has returned to this world with the Impostors series. The original Uglies series is set to become a Netflix movie in late 2024.

Another notable work is the Leviathan trilogy, a steampunk retelling of World War I, which is becoming an anime series in 2025 on Netflix.

His collaborations include the Zeroes trilogy, with Margo Lanagan and Deborah Biancotti, and the Midnighters trilogy. Standalone works by Westerfeld include novels set in contemporary New York: So Yesterday, Peeps, The Last Days, and Afterworlds.

Westerfeld's accolades include the Philip K Dick Special Citation, Aurealis Award, and Victorian Premier’s Award. He has contributed to various publications, including Nerve, BookForum, and Nature, and has experience as a ghostwriter.

Outside of writing, Westerfeld has worked as a factory worker, substitute teacher, textbook editor, and software designer. He resides between New York City and Sydney, Australia, with his wife, fellow writer Justine Larbalestier.