Tom Tjaarda (born Stevens Thompson Tjaarda van Starkenburg; July 23, 1934 – June 2, 2017) was an American automobile designer noted for his work on a broad range of automobiles — estimated at over eighty — from exotic sports cars including the Ferrari 365 California and De Tomaso Pantera to high-volume popular cars including the first generation Ford Fiesta (1976) and the Fiat 124 Spider (1966).

For his work, Tjaarda was honored at the 1997 Pebble Beach Concours d'Elegance as well as the 1997 Concorso Italiano.

Jalopnik called Tjaarda "one of the defining automotive designers of the 20th century." Noted automotive designer and journalist Robert Cumberford called Tjaarda "one of the world’s most accomplished Italian car designers." Car Design News called him "one of the great unsung heroes of the car design world."

Tjaarda was born in Detroit, the son of Irene Tjaarda and Dutch auto designer John Tjaarda (born Joop Tjaarda van Starkenburg, 1897–1962), designer of the 1935 Lincoln Zephyr.

Tjaarda's parents divorced in 1939 and he lived with his mother in Detroit. Tjaarda studied high school in Birmingham High School, Birmingham, Michigan (1953 renamed to Seaholm High School).

Tjaarda studied Architecture at the University of Michigan and presented an automobile (a sport station wagon) rather than building design for his senior thesis — winning an internship at Carrozzeria Ghia, the renowned Italian design house.

In 1958, he moved to Turin, Italy, where his career began and where he continued to live and work.

Tjaarda started his career at Ghia with the Innocenti 950.