The Barber of Seville, or The Futile Precaution (Italian: Il barbiere di Siviglia, ossia L'inutile precauzione) is an opera buffa in two acts by Gioachino Rossini with an Italian libretto by Cesare Sterbini. The libretto was based on Pierre Beaumarchais's French comedy Le Barbier de Séville (1775). The première of Rossini's opera (under the title Almaviva, o sia L'inutile precauzione) took place on 20 February 1816 at the Teatro Argentina, Rome.

Rossini's Barber has proven to be one of the greatest masterpieces of comedy within music, and has been described as the opera buffa of all "opere buffe". Even after two hundred years, its popularity on the modern opera stage attests to that greatness.

The premiere of Rossini's opera was a disastrous failure: the audience hissed and jeered throughout, and several on-stage accidents occurred. However, many of the audience were supporters of one of Rossini's rivals, Giovanni Paisiello, who played on mob mentality to provoke the rest of the audience to dislike the opera. Paisiello had already composed The Barber of Seville and took Rossini's new version to be an affront to his version. In particular, Paisiello and his followers were opposed to the use of basso buffo, which is common in comic opera. The second performance met with quite a different fate, becoming a roaring success. The original French play, Le Barbier de Séville endured a similar story, poorly received at first only to become a favorite within a week.