[2][3] Nominated for the Academy Award for Best Film Editing on four occasions, she is remembered for editing three of director John Ford's best known movies, including Stagecoach (1939) and My Darling Clementine (1946), which film critic Roger Ebert called "Ford's greatest Western".

At Fox, she and Loeffler were part of an editorial team that also included, at one time or another, Barbara McLean, Robert Simpson, William Reynolds and Hugh S.

[citation needed] In the 1940s, Spencer edited Alfred Hitchcock's Foreign Correspondent (1940) and Lifeboat (1944); the latter featured a particularly feisty and well-edited Tallulah Bankhead performance.

Spencer also edited director Elia Kazan's feature film debut, A Tree Grows in Brooklyn (1945).

Variety's Eileen Kowalski notes that, "Indeed, many of the editorial greats have been women: Dede Allen, Verna Fields, Thelma Schoonmaker, Anne V. Coates and Dorothy Spencer.