Harold Pinter’s The Birthday Party was the playwright’s first commercially-produced, full-length play. He began writing the work after acting in a theatrical tour, during which, in Eastbourne, England, he had lived in filthy insane digs. There he became acquainted with a great bulging scrag of a woman and a man who stayed in the seedy place. The flophouse became the model for the rundown boarding house of the play and the woman and her tenant the models, respectively, for the characters of Meg Boles and Stanley Webber. In an earlier work, The Room, a one-act play, Pinter had worked on themes and motifs that he would carry over into The Birthday Party and some of his succeeding plays. Among these themes are the failure of language to serve as an adequate tool of communication, the use of place as a sanctum that is violated by menacing intruders, and the surrealistic confusions that obscure or distort fact. Pinter would later marvel at the fact that in London the play was completely massacred by the critics but noted that it was the only maltreatment he had received from reviewers and that it never dimmed his interest in writing. The work, in fact, became the dramatist’s first full-length comedy of menace, a group of plays that secured Pinter’s reputation as a premier, avant-garde playwright. By the mid-1960s,the burgeoning appreciation of absurdist drama and the success of other plays by Pinter, including The Dumbwaiter (1959) and The Caretaker (1960), had secured for The Birthday Party a reputation as a classic in the dramatic genre that literary critic Martin Esslin dubbed the Theatre of the Absurd. This paper, therefore, attempts to look into The Birthday Party as a landmark absurdist play. Keywords: themes and motifs, intruders, surrealistic confusions, first full-length comedy of menace, avant-garde playwright, absurdist play