Sweden’s dependence on maritime transport is evident by the fact that approximately 60% of the freight to and from the country is carried by sea. Given this dependence, maintaining efficient and effective maritime and port services is critical to trade outcomes. However, maritime and port actors face operational constraints and stricter environmental requirements. Around 15% of the vessels that call Swedish ports experience a median delay of 13 hours, resulting in operational inefficiencies. Furthermore, stricter environmental measures are expected to increase the cost of shipping by 10-40%. One measure for addressing these challenges is the implementation of Just-in-Time arrival in port calls that enhances operational efficiency and reduces emissions from the sector. These benefits are obtained by coordinating the sailing speeds of the vessels with the availability of services at the port of destination. Existing research has mainly focused on estimating the potential of Just-in-Time to reduce fuel consumption and emissions from maritime transport. However, the process through which Justin- Time is implemented is characterized by interdependencies among port call actors. Realizing the potential of Just-in-Time requires effective management of these interdependencies through appropriate coordination mechanisms. Research that identifies these coordination mechanisms and elaborate upon their adoption and use is limited, leading to a lack of understanding regarding how the potential of Just-in-Time can be realized in practice. Hence, this thesis focuses on identifying and elaborating upon the coordination mechanisms that required to implement and realize the benefits of Just-in-Time. 

To understand how the benefits of Just-in-Time can be realized in practice, this thesis deploys qualitative and quantitative methods. Case and process studies with pioneering Swedish ports in the implementation of Just-in-Time were conducted. Empirical data were gathered from the ports of Gothenburg, Gavle, and Oxelosund during 2020-2025 through interviews, observations, and archival data. Additionally, quantitative modeling was used to estimate potential fuel and emissions savings associated with implementing JIT in the Swedish context. 

Findings indicate that Just-in-Time benefits several port-call actors: owners and charterers realise fuel savings, emissions reductions, and compliance, while terminals and port authorities gain improved service quality, reliability, and environmental performance. To realize these benefits, the thesis proposes a set of coordination mechanisms to manage the interdependencies among actors: port community systems, time-slot berth allocation policies, contractual clauses, pilot exemption certifications, and vessel performance systems. These mechanisms facilitate the implementation of Just-in-Time either individually or by being complementary to each other. The focus has been primarily on the adoption of port community systems and time-slot berth allocation policies. The configurations of port community systems are presented, and the findings reveal that its adoption is a prerequisite for port authorities to adopt time-slot berth allocation policies. Furthermore, successful adoption relies on an inter-organizational change management approach that involves and engages port call actors. By involving and engaging port call actors in the adoption processes, they contribute to making the configurations and use of these mechanisms more effective. Barriers that negatively impact the adoption and effective use of these two mechanisms also emerged. These were regulatory constraints, low digital maturity, information deficiencies, and commercial dependencies. Their root causes arise both intra-organizationally (within port authorities) and inter-organizationally (across the wider port community). The thesis concludes that successful JIT implementation requires coordinated alignment across technological, operational, commercial, and regulatory domains.