This chapter aims to increase awareness related to the assessment of embodied greenhouse gas emissions (GHGE) of the built environment in Australia—a critical step to achieve meaningful emissions reduction. A summary of existing methods, data, tools, guidance and gaps in quantifying embodied GHGE in the Australian built environment is provided. A quick evaluation of embodied GHGE is an important aid for the design decision-making process within the architecture, engineering and construction industries. The newly developed Embodied Carbon Explorer (ECE) online tool is introduced to rapidly assess embodied GHGE for built environment projects with National Carbon Offset Standard-performance objectives. A case study using the ECE tool is described that quantifies the total carbon footprint of Australia’s construction industry and identifies the main contributors of embodied GHGE.