This article argues for a more incisive understanding of regional development through examining and explaining the effects of simultaneous strategic coupling. Circumventing firm-centric approaches that underplay dynamic intra-regional asset formation and matching with global production networks (GPNs), this article spotlights how simultaneous coupling with multiple GPNs within the same region is constituted by and generates new interactive effects between preexisting industrial paths in the region and GPNs. Drawing evidence from a decade-long case study of endogenous asset reconfiguration to embed GPNs in Guangdong, China, this article presents a new framework for examining how simultaneous strategic coupling contributes to regional development. Premised on an evolutionary approach that incorporates the constitutive effects of intra-regional path co-evolution, this framework advances GPN research by highlighting how uneven development within a subnational region is not only shaped by lead firm power but is also actively re-defined by regional actors embedded within different industrial paths.