This research concerns the delivery of sustainable building projects. These projects are defined as those which either attempt to achieve green ratings or are claimed to address certain sustainability issues. A key focus is to examine how the client's vision for sustainability is achieved or compromised by the practicality of construction. Two sustainability rating systems, the Australian Green Star and the Living Building Challenge from the U.S. are discussed. This research examines two projects; one university multipurpose building (SMART Infrastructure Facility); and an advanced research facility, the Sustainable Buildings Research Centre (SBRC). The methodology used is semi-structured interviews of key participants and stakeholders for the two university building. The outcome of this research indicates that environmental rating systems are useful tools to construct reasonably sustainable buildings. Many interviewees, however, believe that for their next projects the concern would be to continue to construct sustainable buildings but not necessarily by following the strict criteria and reporting requirements of the environmental rating system.