One of the most fascinating things about researching ports and studying financial, social and human relations in and around port spaces is that ports are places on the edge (Weaver, 2020): the edge of the sea; the edge of the city; the edge of the coast; the edge of borders. As outlined in the introduction, ports sit at the intersection of the port-city and land-sea divide, occupying a quintessentially ‘liminal’ space where security issues cannot be understood and addressed as problems of the marine or hinterland environment alone (Bueger and Edmunds, 2017; Weaver, 2020). Sergi and Storti capture this sentiment in their concept of the port as a ‘duplex’ space, at once a ‘border space’ a ‘gate’, as well as a ‘space for global trade’ (Sergi and Storti, 2020). In this book, we refer to ports as ‘multivalent’ spaces to highlight how many different dimensions they occupy. The study of port security is the study of global economic opportunism, as much as it is the study of border controls and policing.

Together, the themes discussed in this book bring into question the extent to which port security is a site-specific, municipal, federal, national and even international security objective, a tension felt by the actors responsible for governing and policing them. Much of the research referenced in this book has been carried out in close collaboration with security professionals and law enforcement active in ports; the Secur. Port workshop, interviews with practitioners and all the other knowledge exchange events that the authors have organized and participated in are embedded in its findings and perspectives.

In order to unpack all that this entails, each chapter in this book looked at various aspects of life, politics and economy in the port space. The book has taken a practical look at some of these junctures and the relationships that port spaces produce, blend and enrich across the port-sea and port-city interface. The result is a panacea of interdisciplinary discussions that all paint a complex – and therefore fittingly non-final – picture.