MRI''s avtivities are organised into three main sections: Environment Section, Resources Section and Advisory Section.

Marine Environment Section
A large part of the sections work deals with environmental conditions (nutrients, temperature, salinity) in the sea, marine geology, and the ecology of algae, zooplankton, fish larvae, fish juveniles, and benthos.

Amongst the larger projects undertaken within the Environmental Section are investigations on surface currents using satellite monitored drifters, assessment of primary productivity, overwintering and spring spawning of zooplankton, studies on spawning of the most important exploited fish stocks.

Marine Resources Section
Investigations are undertaken on the exploited stocks of fish, crustaceans, mollusks and marine mammals. The major part of the work involves estimating stock sizes and the total allowable catch (TAC) for each stock.

Examples of some large projects within the Marine Resources Section are annual ground fish surveys covering the shelf area around Iceland and surveys for assessing inshore and deep-water shrimp, lobster, and scallop stocks. The pelagic stocks of capelin and herring are also monitored annually in extensive research surveys using acoustic methods. Further, in recent years an extensive program concentrating on multi-species interactions of exploited stocks in Icelandic waters has also been carried out.

The Fisheries Advisory Section
The Fisheries Advisory Section scrutinizes stock assessments and prepares the formal advice on TAC�s and sustainable fishing strategies for the government.

Supporting departments
Important supporting departments are the Modelling Department, the Electronic Department and the Fisheries Library.
The Modelling Department deals with fisheries and ecologically related mathematical models and is also involved in projects concerning methodological problems in fish stock assessment.
The Electronic Department supervises installation, testing and maintenance of research instruments.
The Fisheries Library collects books and periodicals in all fields of marine sciences which the scientists of the MRI are working.