Six Characters in Search of an Author (Italian: Sei personaggi in cerca d'autore) is a 1921 Italian play by Luigi Pirandello, first performed in that year. An absurdist metatheatrical play about the relationship between authors, their characters, and theatre practitioners, it premiered at the Teatro Valle in Rome to a mixed reception, with shouts from the audience of "Manicomio!" ("Madhouse!") and "Incommensurabile!" ("Incommensurable!"), a reference to the play's illogical progression. Reception improved at subsequent performances, especially after Pirandello provided for the play's third edition, published in 1925, a foreword clarifying its structure and ideas.
The play had its American premiere in 1922 on Broadway at the Princess Theatre, and was performed for over a year off-Broadway at the Martinique Theatre beginning in 1963.