This chapter focuses on the use of spatial technique in key works that span a great deal of Pierre Boulez’s career: Poésie pour pouvoir (1958) for orchestra and tape, Domaines (1968) for clarinet and ensemble, Rituel in memoriam Bruno Maderna (1974–5) for orchestra in eight groups and Répons (1981) for six soloists, live electronics and ensemble. These works are then compared with spatialised instrumental music by his contemporaries, Karlheinz Stockhausen, Karel Goeyvaerts, Iannis Xenakis and Luigi Nono, which will shed light on Boulez’s specific approach to this artistic practice. Boulez’s unique contribution to the history of spatialisation lies in the strong articulatory function he ascribed to this performance practice. He created a typology of sonic movements that clarify the structural relationships of his spatialised works.

The new music festivals at Donaueschingen and Darmstadt and Boulez’s Domaine Musical concert series were formative for Boulez’s development as a composer, conductor, writer and institution-builder in the 1950s and 1960s. The Donaueschingen festival was significant for premieres of Boulez’s music, including ‘Tombeau’, the final section of Pli selon pli, which was performed in part there in 1959. Boulez’s attendance was intermittent at the Darmstadt new music courses, but he nevertheless interacted there with key figures from the serial generation, such as Karlheinz Stockhausen and Luigi Nono, and Darmstadt was the venue where Boulez first delivered the lectures that were published later as Boulez on Music Today. Boulez created his own concert series in Paris, the Domaine Musical, which he oversaw from its inception in 1953 until 1967, with the aim of performing key works from the first phase of musical modernism, along with music composed by his own generation.

Keeping track of how appreciation and understanding of Tristan und Isolde has evolved, in live performance, recording and scholarly studies, is a formidable task. One path through the labyrinth is opened up by Wagner’s poetic text, in which the title characters express their disorientation, their alienation from communal norms. Stage directors and musicological commentators alike have found ways of dramatising the particular tensions between conformity and nonconformity that encapsulate the drama’s representations of love and death, in settings that balance magical interventions (the love potion) against the worldly intrusions of King Marke and his entourage. Surveying and critiquing accounts of the role that Tristan und Isolde has played at the heart of fundamental changes to musical form and style since the 1860s reinforces the value of arguing that the continued presence of modernist qualities in contemporary music – works by Schoenberg, Nono, Henze, Andriessen and Anderson are instanced - is a direct consequence of Wagner’s materials and methods, particularly in Tristan.

Mahler’s influence among composers intensified steadily over the course of the twentieth century. Within the Austro-German orbit, his impact is evident in the music of figures as varied as Kurt Weill, Hans Werner Henze, and Dieter Schnebel. Further afield, by the mid-1920s a distinguished array of composers including Aaron Copland and Dimitri Shostakovich had begun to engage seriously with Mahler’s music. This trend would continue in the second half of the twentieth century, with the renewed attention paid to Mahler outside Central Europe giving rise to an even more diverse group of followers, including those eager to find emancipation from some of the more influential strands of postwar modernism: George Crumb, George Rochberg, Luciano Berio, Luigi Nono, Pierre Boulez, Peter Maxwell Davies, Michael Finnissy, and Jonathan Harvey. These are surveyed here with particular attention to the diverse ways in which Mahler’s influence expressed itself.