The research project "Investigating Musical Performance: Comparative Studies in Advanced Musical Learning" was devised to investigate how classical, popular, jazz and Scottish traditional musicians deepen and develop their learning about performance in undergraduate, postgraduate and wider music community contexts. The aim of this paper is to explore the findings relating to attitudes towards the importance of musical skills, the relevance of musical activities and the nature of musical expertise. Questionnaire data obtained from the first phase of data collection (n=244) produced evidence of differences and similarities between classical and non-classical musicians. While classical musicians emphasised the drive to excel musically and technically and prioritised notation-based skills and analytical skills, non-classical musicians attached greater importance to memorising and improvising. Regardless of genre, the musicians all considered practical activities such as practising, rehearsing, taking lessons and giving performances to be relevant. However, while classical musicians attached greater relevance to giving lessons and solo performances, their non-classical colleagues considered making music for fun and listening to music within their own genre to be more relevant. Some underlying processes that may have accounted for the differences in attitudes are explored, including musical influences, age of initial engagement with music and educational background. Points of similarity and differences are discussed, and possibilities for the two musical trajectories to inform and learn from each other are highlighted. (Contains 3 figures, 8 tables and 1 note.)