Abstract: Since 2000 Melbourne has grown faster than Sydney in population and employment. This is despite Sydney’s advantages in 2000 in having greater prominence as a global city, with stronger finance and advanced producer services sectors, and high visibility from hosting the Olympic Games. The paper examines a number of hypotheses as to why Melbourne grew more despite such initial Sydney advantages. Depressed global conditions for Sydney’s global sectors, especially finance and tourism, are the basis of an initial hypothesis. Higher housing and land costs in Sydney are also hypothesised to have reduced housing construction and land-intensive activities such as manufacturing and logistics, and reduced growth in immigration, tourism and international student intakes, relative to Melbourne. Sub-hypotheses as to why there were higher housing and land costs in Sydney are examined, together with the notion of a possible Melbourne housing ‘bubble’. Lower state spending on tourism and inward investment in Sydney, coupled with less effective state development administration and complacency, are also incorporated into hypotheses. Differences between the cities in transport performance are additionally considered as a causative factor. Finally, the potential influence of a mooted more complex planning system in Sydney is examined. The paper uses ABS 4- digit employment data and housing price data, airline traffic trends, Productivity Commission reports and newspaper reports, inter alia, to test hypotheses.