Some 180 areas where one or more of the maritime zones of two States overlap have not yet been delimited by a boundary. It is not easy to see what can be done or what cannot be done in overlapping EEZs or continental shelves. This is because rights or obligations are not clearly prescribed with respect to overlapping zones under rules of UNCLOS. The study looks at the concept and problems of overlapping maritime zones and analyzes the provisions regarding overlapping maritime areas to see obligations of States under UNCLOS. Obligations of States are laid down in UNCLOS, with regard to overlapping maritime zones. The obligation on States in terms of overlapping territorial seas is clear, as Article 15 of UNCLOS requires States concerned not to extend their territorial sea beyond the equidistance line unless there are special circumstances or issues of historic title. Articles 74 and 83 of UNCLOS concerns overlapping EEZs and continental shelves. The States concerned have a positive obligation to enter into negotiations to try to reach an agreement on the boundary. Where they are unable to reach such an agreement within a reasonable period of time, they shall resort to the dispute settlement procedures of Part XV of UNCLOS. Pending an agreement, States concerned have another oblig...