Kirsten "Kiwi" Smith (born 12 August 1970) is an American screenwriter and novelist. She wrote most of the screenplays with her screenwriter partner Karen McCullah Lutz. Most of the scripts seems to follow the girl Power movement of the late 1990s and early 2000s.

Smith got her official start as a screenwriter in 1997 by selling 10 Things I Hate About You as a spec screenplay. Shortly thereafter, the movie was green-lit, starring then-unknowns Heath Ledger and Julia Stiles, and it was shot in Tacoma, Washington, near Smith's hometown.