Thesis (MMus (Music))--University of Stellenbosch, 2009. / Arnold van Wyk was a composer and a pianist. He recorded his largest work for piano, Night Music (1958), on LP in 1963. Steven de Groote performed Night Music on 21 July 1984 at the Cheltenham International Festival of Music. This live performance was broadcast on BBC Radio 3 on 24 September 1984 and a copy of this broadcast exists in the Arnold van Wyk collection in the J.S. Gericke Library at Stellenbosch University. Night Music is a perfect example of Van Wyk’s compositional techniques for the keyboard. It demands a considerable musical imagination and piano technique from the performer. The score of Night Music contains many detailed instructions regarding the different musical parameters and it also encloses unusual terms such as glacial or lugubre. It shows that the composer is extremely concerned to control all aspects of the performance and expects great depth of interpretation of the performer. Analysing the score of Night Music together with a performance by the composer enables one to consider two versions of “authenticated text”. The comparison between Arnold van Wyk’s recording, score and Steven de Groote’s performance allows the researcher to draw conclusions about score fidelity as a condition for “authenticity” in performance. Therefore, the primary aim of this research project is to yield interesting perspectives on notions of authenticity in performance with regard to these two particular performances of Night Music. The main body of this thesis consists of four chapters. In Chapter One a philosophical discussion about authenticity in performance is presented. Chapter Two focuses on the contextualisation of the work under discussion, including the reception and a short analysis of Night Music. It is followed by Chapter Three which compares the pianism of Arnold van Wyk and Steven de Groote. These latter two chapters form the background of the comparative performance analysis of the renditions of Night Music by these two performers which are presented in Chapter Four. Through the careful comparative analysis of Arnold van Wyk’s and Steven de Groote’s performances of Night Music it was possible to observe that a composer can present a version of his work that departs quite radically from the score. As “authenticity in performance” strives to honour the composer’s intentions as notated in the score, this discrepancy illustrates the controversial nature of the discourse on the “authentic” in music.