This chapter explores the importance of adapting for a composer, whether that be in their own creative practice (for example by adapting stories for the stage or screen) or in their engagement with others’ works through arrangements or orchestrations. It considers what a suitable definition of adaptation might be, and where the boundaries of originality might lie in adapting someone else’s work, before arguing that adaption necessitates a valuable set of composition skills that require us to think actively and conscientiously about our role in history and society.

This chapter examines the use of borrowed material; that is, basing polyphony on existing music, whether plainchant or polyphony previously composed. The techniques described have intentionality in common: cantus firmus treatment of varying degrees of strictness, including paraphrase, ‘imitation’ technique (formerly known as ‘parody’), and more allusive forms. Special consideration is given to the different motivations for the practice (dating back to the origins of polyphony itself), ranging from symbolic or allegorical representation to emulation and competition between composers. Picking up from Chapter 8, the family of ‘L’Homme armé’ Masses offers a case-study of these relationships, but the practice of musical borrowing transcends any single genre, type, or destination. Equally remarkable is the possible range, scale, and scope of allusion, from overt quotation over an entire work to passing reference or evocation of a given technical parameter in ways that may not be directly audible. Finally, different types of borrowing reconfigure the relationship between composer, performer, and audience; these changing dynamics are closely considered.

In 2014, James MacMillan established a music festival in his hometown of Cumnock, calling it The Cumnock Tryst.MacMillan has explained that the festival’s title was inspired by a simple love song he wrote in 1984 called ‘The Tryst’, setting a poem by William Soutar. So brief is this song that it might have fallen into obscurity. Yet its melody has infused no fewer than twelve works in MacMillan’s oeuvre, spanning over a quarter of a century. The scope of genres in which it appears is striking: from a folk song to an early orchestral tone poem; from a large-scale setting of the Christian passion to a congregational mass setting. Although MacMillan has reused musical material from numerous works, The Tryst is unarguably the most important and fruitful of these reincarnations, revealing the most significant degree of his self-retrospection. The broad variety of musical contexts in which the song features demands a range of interpretations to understand the various ‘meetings’ MacMillan proposes with each use of the melody, from the erotic, to the sacred, to the communitarian. By examining these ‘Trystian’ works, we may come to appreciate the extent to which this love song has permeated his career to date.

It may seem slightly incongruous to look specifically at the liturgical music of James MacMillan, a composer for whom the liturgy has had such bearing on his entire compositional ethos and personal philosophy. For the liturgy has provided the impulse for both MacMillan’s large corpus of sacred choral pieces, and the bulk of his instrumental works. However, this over-riding influence of the liturgy makes an in-depth look at the purely liturgical works all the more relevant: here we find the composer stripped of the myriad of allusions that characterise other works and find him working in a specifically explicit manner. The chapter looks at MacMillan’s extant Mass settings, though will focus mainly on the setting from 2000 as the most succinct appraisal of his assimilating of the vernacular. It will also look at his Magnificat (1999), Nunc Dimittis (2000), Jubilate Deo (2009) and Te Deum settings, showing some of the composer’s current pre-occupations with the borrowing and recycling of material and ideas relating to form and through-composition.