This technical report summarises the results of detailed transport network modelling undertaken by Veitch Lister Consulting on behalf of Infrastructure Australia for the 2019 Australian Infrastructure Audit. The modelling was undertaken for the nation’s six largest urban conurbations. A conurbation is defined as an extended urban area. In the case of this report it applies to Australia’s six largest capital cities and the neighbouring satellite cities and regions. These range from close to 6 million residents in the combined Sydney, Hunter and Illawarra regions, to 450,000 people living in the ACT and Queanbeyan. The assessment reports outcomes for a 2016 base year and forecasts the systems’ performance in 2031.