Since 1984 the six ministerial North Sea Conferences have resulted in a number of high level political commitments to implement the precautionary principle and it is one of the guiding principles of the OSPAR Convention. Originally limited in the OSPAR Convention to the pollution of the marine environment through the introduction of substances and energy, the precautionary principle has been broadened under the ecosystem approach of the OSPAR Commission to encompass all human activities.
By virtue of the precautionary principle, preventive measures are to be taken when there are reasonable grounds for concern that human activities may bring about hazards to human health, harm living resources and marine ecosystems, damage amenities or interfere with other legitimate uses of the sea, even when there is no conclusive evidence of a causal relationship. A lack of full scientific evidence must not postpone action to protect the marine environment. The principle anticipates that delaying action would in the longer term prove more costly to society and nature and would compromise the needs of future generations.
An important milestone for marine conservation was the introduction of the precautionary approach to international and European fisheries management, including the Agreement for the Implementation of the United Nations Conventions on the Law of the Sea of 10 December 1982 relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks (UN Fish Stocks Agreement).