This article examines the potential contribution of value-adding services (VAS) to port logistics strategy development in order to enhance competitiveness in the face of increasing competition between ports. On the basis of an empirical study taking the critical-realist approach of mixed methods' research and using data from multiple case-study ports in both developed and developing countries, the relevance and deployment of VAS are assessed with a view to facilitating port strategy decisions. This study addresses the paucity of VAS investigations in the maritime logistics literature and examines the potential contribution of VAS to port competitiveness from the perspective of port users. Results demonstrate that the most readily available and accessible VAS are transport services, followed by warehousing and water supplies. The article concludes that VAS have the potential to both attract port users and retain them.