<p>Despite a growing body of literature on the knowledge city, the concept still lacks concreteness and specificity. It remains too broad to underpin focused empirical studies and, further, to inform nuanced policymaking and planning. This conceptual ‘broadness’ calls for clarity and precision in defining and measuring knowledge cities. In this study, we construct a knowledge city index—which conceptually and methodologically builds upon and extends the extant literature—to capture a city’s knowledge ‘integrativeness’ and knowledge‘intensiveness’. We apply this index to measuring 25 cities in Australia. The results offer an enhanced understanding of Australian cities in transition to the knowledge economy and reveal a typology of them according to their knowledge performance. Based on the approach and results, we argue that ‘the knowledge city’ requires new thinking that goes beyond the conventional perception of scale and administrative boundary of a city and, instead, focuses on its knowledge core and flow. We further argue that ‘the knowledge city’ provides new opportunities for smaller cities and regional centres—which have been traditionally disadvantaged by scale and geographical location—to grow competitiveness through capitalising on the knowledge economy and new technology and to fulfill the United Nations’ Sustainable Development Goal (SDG) 11 Sustainable Cities and Human Settlements.</p>