Signor Deluso

Signor Deluso
Opera by Thomas Pasatieri
Scene from Molière's comedy Sganarelle, ou Le Cocu imaginaire, the inspiration for the opera's libretto
Librettist	Thomas Pasatieri
Premiere	27 July 1974 (1974-07-27) Madeira School, McLean, Virginia

Signor Deluso is an opera buffa in one act composed by Thomas Pasatieri. The English-language libretto, written by the composer, is loosely based on Molière's 1660 comedy Sganarelle, ou Le Cocu imaginaire ("Sganarelle, or The Imaginary Cuckold"). It premiered on 27 July 1974 at the Madeira School auditorium in McLean, Virginia performed by the Wolf Trap Opera Company. It has been subsequently performed many times by various small opera companies in the United States and Europe. In a review of a 2008 revival in Washington, D.C., Anne Midgette described it as "an exuberant sendup of over-the-top comic opera plots, filled with effusive lovers leaping with alacrity to wrong conclusions in floods of extreme vocalism."

A commission from the Juilliard School of Music, the opera was composed when Pasatieri was 28. He chose the subject after reading Molière's Sganarelle, ou Le Cocu imaginaire. He wrote the libretto himself and completed the score in two months. The opera had its world premiere on 27 July 1974 in a production by the Wolf Trap Opera Company directed by David Bartholomew and conducted by John Moriarty. It was performed as a double bill with Pasatieri's one-act opera Calvary which had premiered in 1971. The New York premiere of Signor Deluso followed later that year performed by the Manhattan Theatre Club. The Juilliard School staged it in 1979.

The opera is scored for seven solo singers and a small orchestra (flute, oboe, clarinet, horn, piano, violin, viola, and cello). Its short running time (30 minutes) and chamber opera format have made it particularly popular with small opera companies and music schools. By 2006, Signor Deluso had received over 8000 performances and had been performed in the United States, Finland, Germany, Sweden, and Korea. A recording of the work performed by Opera Company of Brooklyn was released by Albany Records in 2006.