Good Environmental Status is a qualitative description of the state of the seas that the European Union's Marine Strategy Framework Directive requires its Member States to achieve or maintain by the year 2020. ^[1] Good Environmental Status is described by 11 Descriptors:

• Descriptor 1. Biodiversity is maintained
• Descriptor 2. Non-indigenous species do not adversely alter the ecosystem
• Descriptor 3. The population of commercial fish species is healthy
• Descriptor 4. Elements of food webs ensure long-term abundance and reproduction
• Descriptor 5. Eutrophication is minimised
• Descriptor 6. The sea floor integrity ensures functioning of the ecosystem
• Descriptor 7. Permanent alteration of hydrographical conditions does not adversely affect the ecosystem
• Descriptor 8. Concentrations of contaminants give no effects
• Descriptor 9. Contaminants in seafood are below safe levels
• Descriptor 10. Marine litter does not cause harm
• Descriptor 11. Introduction of energy (including underwater noise) does not adversely affect the ecosystem