Maritime transportation is the most obvious choice for industries to transport large amounts of liquid or dry bulk products over long distances. Often, the bulk products are stored as inventories at or near the loading and unloading port. A maritime inventory routing (MIR) problem is a planning problem where the ship operator has the responsibility not only for the ship routing and scheduling, but also for the inventory management at one or both ends of the sailing legs. Here we review research on MIR and extension problems during the last two decades. Since this problem was first introduced in 1987, we have found over a hundred publications on it in refereed journals. Most of them consider static and deterministic problems even though uncertainty plays an important role in MIR. We also found that most recent research on this field focuses more on theoretical contributions, rather than on the real problems as in previous studies. However, future high-impact research remains wide open and provides challenging opportunities.