Emerging synergies in polycentric cities? Exploring the impact of intercity cooperation on labour market integration in the Yangtze River Delta, 2014–2021

The creation of regional synergies has received much attention, both as an analytical framework and a normative goal in urban and regional development studies. One of the key mechanisms underlying synergies - cooperation - is particularly relevant for understanding how cities and their labour markets regionally integrate. Yet city cooperation remains poorly understood in conceptual and empirical terms. In addition, it is unclear to what extent intercity cooperation and the effects of the ensuing labour market integration are consistent across cities with different urban structures. Drawing on intercity patent transfer data, we explore the presence of synergies by examining cooperative relations between cities. Using a longitudinal analytical framework, we focus on China's Yangtze River Delta megacity-region from 2014 to 2021 to explore the impact of intercity cooperation on labour market integration within polycentric urban settings. Our analysis reveals that: (1) intercity cooperation derived from technology linkages has a U-shaped effect on labour market integration and (2) polycentric structures not only contribute to this integration but also moderate the relationship between intercity cooperation and labour market dynamics. We reflect on the broader implications of our empirical findings for regional development strategies and discuss possible avenues for future research.