The International Association of Classification Society (IACS) is a non-governmental technical organization currently made up of 12 members of the Marine Classification Society. More than 90% of the world's cargo ship tonnage meets the classification criteria set by IACS member associations.

What is the importance of IACS?

Dedicated to the safety of ships and cleanliness of the seas, IACS makes a unique contribution to maritime safety and regulation through technical support, conformity verification, and research and development.

IACS derives from the recommendations of the 1930 International Convention on Load Lines. The Convention encouraged cooperation between classification societies to ensure "maximum uniformity in the application of strength standards based on freeboard".

After the Congress in 1939 the Italian Naval Register (Registro Italiano Navale, RINA) held the first meeting of a large association attended by ABS, BV, DNV, GL, LR and NK, who agreed to further cooperation between the associations.

The second major meeting of the class society, held in 1955, led to the creation of working groups on specific topics, and in 1968 IACS was formed at seven major societies.

IACS was founded on 11 September 1968 in Hamburg, Germany and is currently headquartered in London.

In 1969, the IMO granted IACS advisory status. Since then, the number of members has grown to 12. DNV and GL were merged in 2013. The new organization was called DNVGL but was changed to DNV in 2021.

Although IACS is a non-governmental organization, it also plays a role in the International Maritime Organization (IMO), where IACS provides technical assistance and guidance and develops uniform interpretations of international regulations developed by IMO member countries. Once adopted, these interpretations are applied by each IACS member association when verifying compliance on behalf of the accrediting flag State.

IACS remains in consultation with the IMO and remains the only non-governmental body with an observer capacity to develop and implement technical rules that reflect the goals embodied in the IMO Convention. The relationship between the International Maritime Regulations developed by IMO and the requirements of the classification rules for hull structures and basic engineering systems is codified in the International Convention on the Safety of Life at Sea (SOLAS).

IACS is governed by a committee, each member of which is represented on the committee by a senior official. The position of chairman of the council rotates annually among its members. The committee reports to the General Policy Group (GPG), which is made up of senior management representatives from each member society. The GPG develops and implements actions that embody the Commission's policies, directions and long-term plans. The GPG is chaired by a member who presides over the committee. Most IACS technical development work is performed by several working groups (WPs) made up of technical, engineering, research, or quality control personnel from member associations.