SEA is a process to ensure that significant environmental effects arising from policies, plans and programmes are identified, assessed, mitigated, communicated to decision-makers, monitored and that opportunities for public involvement are provided.

SEA has become an important instrument to help to achieve sustainable development in public planning and policy making. The importance of SEA is widely recognised. Particular benefits of SEA include:

• To support sustainable development;
• To improve the evidence base for strategic decisions;
• To facilitate and respond to consultation with stakeholders;
• To streamline other processes such as Environmental Impact Assessments of individual development projects.

SEA is a generic tool which can be used in a variety of situations. A particular form of SEA is being introduced by the European Union Directive 2001/42/EC. This requires national, regional and local authorities in Member States to carry out strategic environmental assessment on certain plans and programmes that they promote. Click here for more information on when an SEA is required.

In the UK , various approaches to conducting strategic assessments and appraisals are already well developed including environmental appraisal of local authority land-use plans and sustainability appraisal of regional planning guidance. These existing approaches are being strengthened through implementation of the SEA Directive.

Conducting an SEA is an iterative process which should be carried out alongside the development of the plan or programme. Click here for information on the key stages involved in conducting an SEA.