The Works of Giuseppe Verdi is the first critical edition of the composer’s oeuvre. Together with his operas, the series presents his songs, his choral music and sacred pieces, and his string quartet and other instrumental works. This edition of Messa da Requiem is based on Verdi’s autograph score and other original sources. The appendices include two pieces from the compositional history of the Requiem: an early version of the Libera me, composed in 1869 as part of a collaborative work planned as a memorial to Rossini, and the Liber scriptus, which in the original score of the Manzoni memorial Requiem was composed as a fugue for chorus. The introduction to the score traces the complex compositional and performance histories of the Requiem and discusses the work’s problems of instrumentation and notation, while the critical commentary gives a full description of the sources and an account of all editorial decisions.