When Universal Edition originally published the vocal score of Acts 1 and 2 of Berg's Lulu in 1936 it was generally assumed that the publication of the score of Act 3 would follow in a few months. There was at that time no reason to think otherwise; it was known that Erwin Stein, who had prepared the vocal score of the first two acts for publication, had already completed work on the final act, and the published score of Acts 1 and 2 itself carried a reassuring prefatory note saying that Berg had completed Lulu shortly before his death and that, although large selections of the work remained to be scored, the vocal score of Act 3 would be published in the near future. In the event it has taken almost forty-five years for the score of the final act to appear. Although, thanks mainly to the pioneering work of George Perle, much was known about Act 3 before it finally reached the stage in February 1979, analytical studies of the opera have inevitably concentrated on the music of Acts 1 and 2. Only now, with the publication of the vocal score of Act 3, are we able to examine in any detail the way in which the musical elements exposed in these earlier acts are further developed in Act 3 and to assess the function of these elements in the context of the work as a whole.