For pianists working within the western art music tradition, the ability to perform a large and complex repertoire from memory is almost a prerequisite for a successful career. Memorising and maintaining this repertoire requires considerable practice and can lead to physical overuse syndromes. Additionally, automated motor memory developed via physical practice is not always sufficient for secure recall, often leading to performance anxiety. It is important therefore for professionals to identify optimal practice strategies, and mental rehearsal has been widely advocated as a potential means of enhancing memorisation and performance fluency while at the same time avoiding physical overuse. The results of three studies that examined mental imagery rehearsal by expert pianists, adopting a mixed methods approach, are presented in this thesis. The first was a participant observation study of a course at which eleven advanced pianists learned to use a memorisation technique incorporating deliberate imagery; the study aimed to describe the teaching and learning of specific imagery techniques and to examine the potential advantages and drawbacks of this approach. The second study was an online questionnaire survey of thirty six piano students at UK conservatoires designed to investigate the teaching and implementation of mental rehearsal techniques at advanced training levels; the survey found that despite a widespread awareness of imagery rehearsal as a potentially effective strategy, training in specific techniques was not consistently available, and recommended mental practice strategies were adopted much less consistently than strategies involving physical practice. Finally, an fMRI study of fourteen expert pianists aimed to determine the neural correlates of imagery rehearsal and simulated piano playing. Differences observed in brain activation between tasks suggested increased involvement of working memory processes during mental imagery. The thesis concludes that mental imagery rehearsal techniques are acquired skills that can be taught and improved over time and which have specific advantages over motor learning, but that more pedagogical training is needed in order for these techniques to become fully effective and widely adopted.