The Airport Monitoring Report 2011-12 by the ACCC assesses the performance and quality of aeronautical and car parking services at major Australian airports including Adelaide, Brisbane, Melbourne, Perth, and Sydney. Despite an increase in combined passenger numbers and aeronautical revenues, the overall quality of service diminished, highlighting emerging congestion challenges driven by increased demand for services. The report emphasizes the need for further investment to enhance capacity and addresses ongoing issues with service quality and operational congestion.