Recent research on musical practice has focused on metacognition and the strategies that musicians adopt in their preparations for performance. This study explored the development of metacognition and performance planning strategies in musicians from novice to professional level. Twenty-two professional musicians and fifty-five novices were interviewed about their practising. The novices were also tape-recorded learning and performing a short piece. The professional musicians demonstrated extensive metacognition in relation to their preparations for performance encompassing technical matters, interpretation, and issues relating to learning itself, e.g. concentration, planning, monitoring and evaluation. Although there were similarities in the strategies adopted there was considerable variation because of individual need. In the novice musicians, there was a complex relationship between the development of expertise and the use of planning strategies.