Delineating polycentric megacity regions based on intra- and extra-regional economic transactions between emerging high-tech industries and producer services: a case study on the Guangdong–Hong Kong–Macao Greater Bay Area, China

Polycentric megacity regions (MCRs) have been widely recognised as pivotal engines of economic development, the study of which necessitates scholarly attention to the up-to-date economic dynamics underpinning regional competitiveness and refining spatial divisions of labour. This study aims to delineate functional polycentric MCRs by delving into intra- and extra-regional economic transactions between emerging high-tech industries and producer services, using a case study of the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) in China. Key findings are threefold. First, the functional polycentric development of the GBA MCR based on intra- and extra-regional economic transactions remains at a nascent development stage, reflecting transitional economic restructuring processes. Second, the degree of functional polycentricity of the GBA increases when it upscales from the intra- to extra-regional level. Third, different types of producer services that meet the development needs of emerging high-tech industries play distinctive roles in shaping polycentric development within and beyond the GBA MCR. This study extends an economically grounded understanding of functional polycentric MCRs, nuanced by micro-level heterogeneous economic agents.