Liner shipping accounts for a significant portion of the global seaborne trade and contributes to the development of global trade. The decisions, made by liner shipping companies, can be divided into four groups: (1) strategic level; (2) tactical level; (3) operational level; and (4) real-time. Tactical-level decisions are generally made by liner shipping companies on a medium-term basis (i.e.,
... [Show full abstract] from 3 months to 6 months). One of the most important decision problems, undertaken by liner shipping companies at the tactical level, is the vessel scheduling problem. The vessel scheduling problem focuses on determination of sailing speeds, port times, handling rates at ports, and number of vessels to be deployed for service of the given liner shipping route. Along with the vessel schedule design, there are some other challenging problems, which should be tackled by a given liner shipping company at the tactical level, including fleet deployment, speed optimization, and service frequency determination. Generally, the aforementioned tactical-level decision problems are addressed separately in the existing literature. Some of the studies have integrated multiple decision problems. However, no study has combined the vessel scheduling problem with the three other decision problems (i.e., service frequency determination, fleet deployment, and sailing speed optimization). To address the latter issue, this study proposes a novel holistic optimization model, which incorporates all the tactical-level decision problems in liner shipping. The holistic model aims to maximize the total profit and considers the major cost components, including (1) total vessel operating cost, (2) total vessel chartering cost, (3) total fuel consumption cost, (4) total late arrival cost, (5) total port handling cost, (6) total container inventory costs in sea and at ports of call, and (7) total emission costs in sea and at ports of call. Obtaining optimal results for the highly complicated mathematical model could be a challenge. Hence, potential solution approaches are outlined and will be explored as a part of future research.