Within research on world cities, much attention has been paid to advanced producer services (APS) and their role within both global urban hierarchies and network formation between cities. What is largely ignored is that these APS provide services to firms operating in a range of different sectors. Does sector-specific specialisation of advanced producer services influence the economic geography of corporate networks between cities? If so, what factors might explain this geographical pattern? This paper investigates these theoretical questions by empirically focusing on those advanced producer services related to the port and maritime sector. The empirical results show that the location of AMPS is correlated with maritime localisation economies, expressed in the presence of shipowners and port-related industry as well as APS in general, but not by throughput flows of ports. Based upon the findings, policy recommendations are addressed. © 2010 Urban Studies Journal Limited.