The building industry in Australia has experienced significant growth in recent years, leading to an increase in new building projects and associated stock. While researchers and policymakers propose the circular economy (CE) as an effective system to overcome the conservative approach to design and construction, stakeholders in the Architecture, Engineering, and Construction (AEC) professions face critical challenges in transitioning to circular building practices. This study aims to explore stakeholders’ perceptions of key circular design factors and the main barriers to the adoption of circular building (CB) practices in Australia’s building sector. A qualitative method involving semi-structured interviews was conducted with Australian AEC stakeholders to assess the challenges of adopting CB design factors. Initial findings indicate that among the variety of barriers faced by AEC stakeholders, technical and programming barriers—such as lack of adequate design and construction techniques among disciplines, timing constraints and cost implications—are prominently highlighted. Conversely, collaboration and early contract involvement (ECI) are identified as potential main enablers. The results inform clients and government organisation to recognize the current issues and highlight the need for appropriate actions to address the challenges faced by AEC stakeholders.