Letter from an Unknown Woman is a novella by Austrian writer Stefan Zweig. The work first appeared in the 1 January 1922 issue of the Viennese Neuen Freien Presse, before being published in book form as part of the collection Amok: Novellen einer Leidenschaft. The novella tells the story of an author who, while reading a letter written by a woman he does not remember, gets glimpses into her life story. It is generally considered to be Zweig's most famous work of fiction.