Urban development and renewal is changing the shape and composition of Australian cities, putting increasing pressure on biodiversity, water resources, and human health and well-being. As our cities intensify and expand, there will be further losses to the number and diversity of species and habitats; the ‘nuts and bolts’ of the green infrastructure that makes our cities liveable. This green infrastructure is better known by other names—urban forest, parks and open space, green roofs and living walls. It delivers a suite of ecosystem services, that is, services which nature provides to humanity notionally ‘free of charge’. In 2016, the NSW Environmental Trust commissioned a multi-disciplinary, cross-scale (spatial and temporal), research project to investigate urban ecology renewal in the face of rapid growth in the state’s major cities. The issues of urban ecology renewal were investigated from three perspectives: urban ecology and biodiversity, planning and policy, and built environment. A desktop literature review and series of stakeholder consultations highlighted the gaps and opportunities for improving urban ecology outcomes. Ultimately, a blueprint document based on this evidence base presented recommendations for embedding urban ecology into decision making, from individual lot to the metropolitan scale, and within government policy and planning frameworks. This paper reflects on the findings of the built environment team’s examination of the relationship between the design and management of the built environment and urban ecology, which explored the question: how we can transition to models for the built environment, which conceive of the city as a constructed ecology?