Modernist art music of the interwar period takes its place among other early Australian musical modernisms. It developed within an antipodean modernity transformed by new technologies of transport and communication. Mobility – the movement of people, scores, print journalism and recordings – is central here. Using a conceptual framework informed by transnational historical approaches and expanded understandings of the unsettled and contested concept of modernism, this chapter provides a more generous reading of this musical moment long obscured by the concerns and anxieties of a young nation negotiating its complicated ties to Britain and continental Europe while searching for a distinctive culture. After tracing the emergence of a modernist musical discourse in Australia’s popular press, this chapter looks at the output of a group of composers and various forms of modernist musicking to reveal a transnational community of Australian musicians who actively participated in what can be understood as a modernist music world.