The complete three-act version of Alban Berg's Lulu premiered in 1979.
Berg died in 1935 before fully orchestrating the opera's third act. The first two acts were performed in Zurich in 1937, but that performance did not present the complete work. Friedrich Cerha later completed the orchestration of the third act from Berg's surviving material.
The full three-act version premiered at the Paris Opéra on 24 February 1979. Pierre Boulez conducted, and Patrice Chéreau directed the production. The premiere established the completed form as a major part of the modern operatic repertoire.
The dates are easy to confuse because 1935 is the year of Berg's death, 1937 is the premiere of the incomplete two-act version, and 1979 is the premiere of the completed three-act edition. Those milestones describe different stages in the opera's history.