The MSC Standard is the only internationally recognised set of environmental principles for measuring fisheries to assess if they are well managed and sustainable. 

A well-managed and sustainable fishery protects the fish and the environment in which they live whilst allowing responsible use of the species that come from it. When a fishery is sustainable it means that target fish populations are at healthy levels, sometimes having recovered from being depleted in the past. A well-managed fishery will ensure that there is a future for the industry and all those who depend on the fisheries for their livelihoods.

Any fishery, regardless of its location or size, may apply to be independently assessed against the MSC Standard.

Independent organisations, approved by the MSC to carry out the fishery assessment process, are known as certification bodies.

The three Principles of the MSC Standard are:

Principle 1
The condition of the fish stocks 
This examines if there are enough fish to ensure that the fishery is sustainable.

Principle 2
The impact of the fishery on the marine environment
This examines the effect that fishing has on the immediate marine envirionment including other non-target fish species, marine mammals and seabirds.

Principle 3
The fishery management systems
This principle evaluates the rules and procedures that are in place, as well as how they are implemented, to maintain a sustainable fishery and to ensure that the impact on the marine environment is minimised.