Così fan tutte, ossia La scuola degli amanti, K. 588, is an opera buffa in two acts by Wolfgang Amadeus Mozart. It was first performed on 26 January 1790 at the Burgtheater in Vienna, Austria. The libretto was written by Lorenzo Da Ponte who also wrote Le nozze di Figaro and Don Giovanni.

The Köchel catalogue is a chronological catalogue of compositions by Wolfgang Amadeus Mozart, originally created by Ludwig Ritter von Köchel, in which the entries are abbreviated K. or KV. Its numbers reflect the ongoing task of compiling the chronology of Mozart's works, and provide a shorthand reference to the compositions.