The HHI activity is strategically important to the Republic of Croatia, as defined in the Hydrographic Activity Act, and other laws within the competence of the Ministry of the Sea, Transport and Infrastructure, e.g. the Maritime Code and the Maritime Domain and Seaports Act. HHI is involved in multidisciplinary projects, dealing mainly with the safety of navigation, as well as with other sea-related activities: tourism, protection of the environment (ship damage, places of refuge, sewage systems, etc.), hydro-technical projects, and oil and gas exploitation.

Initiators and beneficiaries of these projects are the Government and ministries of the Republic of Croatia, as well as different business entities engaged in sea-related activities. HHI participates in the scientific projects of the Ministry of Science, Education and Sports, either independently or in cooperation with other scientific institutions. HHI also prepares environmental impact studies and environmental protection reports in compliance with the regulations within the competence of the Ministry of Environmental Protection, Physical Planning and Construction.