Navigational publications provide extensive information relevant for the safety of navigation which cannot be represented on charts. They are published as occasional publications (Sailing Directions, Lists of Lights and Fog Signals, Nautical Tables, Radio Service) or periodicals (Nautical Almanac, Tide Tables). These publications are based on the data collected by the HHI, and other entities engaged in the safety of navigation, being produced according to the recommendations of the International Hydrographic Organisation.

One of the basic activities of HHI is construction, production, publishing and maintenance of charts in analogue format (paper charts) and digital format (ENC). Nautical chart is a representation of a particular navigation area with the main purpose to ensure safe navigation of ships.