Composing has been slighted at all levels of education. Following an analysis of the history and failure of compositional pedagogy for developing musicianship, a new rationale for such pedagogy is presented. This pedagogy is argued to be essential for preparing contemporary musicians and audiences to understand most properly what music ‘is’ and ‘is good for’, and for promoting ever-new conceptions of ‘music’ and of its evolving values. In addition to advancing general musicianship in relation to the standard repertory, the special contribution of pedagogy rooted in composing organised sound pieces is outlined in relation to a new praxial philosophy of music that is challenging the limited and limiting theory of music and its value provided by traditional aesthetic theory. The latter is seen to be a major impediment to new compositional modes that expand musical frontiers, while the praxial theory supports, as well as gains support from, various new attempts to organise sound for expressive and other purposes.