The competitiveness of seaports is affected predominantly by several dimensions and variables present in areas outside the limits themselves. However, decisions made in these areas directly reflect port objectives and strategies. Due to the commercial relations linked to globalization, hinterlands have emerged, others have changed location, and there are also infrastructure changes, due to port congestion and scarcity of land use, as well as the development and emergence of intermodal corridors, among others, causes pointed out in the literature. However, this issue has been addressed relatively moderately in the literature on port operations. In particular, there are gaps to be studied to answer the question of how to know and understand port hinterlands and optimize supply chains. For this reason, this work describes a methodological approach to diagnose, map and define hinterlands of brazilian container seaports. The proposed approach allows researchers, managers and institutions (public and private) to have a resource to assist them in mapping, planning and managing current situations, as well as in analyzing port opportunities, potential and limitations.