By the early 1960s the use of unpainted concrete in many New South Wales (NSW) public buildings represented an aesthetic shift in their architectural expression. Inspired by the architectural discourse associated with the stylistic rubric of the New Brutalism, these buildings were imagined collectively and designed by a figure defined in this thesis as the NSW public agency architect. While some recent histories of the New Brutalism in Australia have analysed this period as a regional variation of a major international movement, this research instead highlights the distinct role of the NSW public agency architect in crafting new public territories. The public agency architect did this by reinterpreting traditional and modern urban design intentions before deploying Brutalist aesthetics as the expressive vehicle. With a sense of design responsibility, these architects had a clear focus on the expression of each new civic or public building. This composite figure in NSW architectural culture consisted of those who worked for the NSW Government Architect and their design branch, the Commonwealth Public Works, as well as private sector architectural practices who designed public buildings. Here the NSW public agency architect deployed Brutalist aesthetics when the scope of their work included projects for the Commonwealth (or the Federal government), the NSW State government, municipal government, public institutions, the Commonwealth Bank, post offices and all the state’s universities. This research examines the viewpoints and formal strategies championed by the NSW public agency architect between 1958 and 1988. The thesis thereby argues that the public agency architect conceptualised various ‘bold and lyrical’ forms for a variety of urban, non-urban and regional NSW settings by spatially framing new public landscapes at a time when a reformed sense of urbanity and the New Brutalism aligned with an ambition to reshape (and communicate) a modern civil society.