Adelaide’s planning history is replete with examples of the adoption and adaptation of leading open space ideas. The making of urban open spaces, beginning with the Adelaide parklands, is a direct result of the publics’ and design professions’ understanding of the benefits that open space affords. The emergence of town planning in the early twentieth century, and in particular the adoption of Garden City and neighbourhood unit ideas and regional planning and the British New Town concepts, contributed to the reconceptualization of open space as a system that underpins the structure of the urban environment. Contrary to nineteenth century practice, increasingly through the second half of the twentieth century, the social, environmental, aesthetic, health and marketing benefits of open spaces, combined with detailed site analysis, determined the development of local open space systems at the beginning of the planning process and as a form of urban infrastructure. This paper investigates the evolution of local open space systems in Adelaide in the second half of the twentieth century, as a consequence of the understood benefits of open spaces and suggests that the local open space systems created in Adelaide at that time were an early form of Green Infrastructure. It does so through the examination of the open space planning in three planned communities – Elizabeth (1950-1965), Noarlunga (1960-1985) and Golden Grove (1974-2003). The paper follows a combined methodological approach that draws on historical-interpretive, qualitative and case study techniques.