Dating from 2003, the policy centres on the concept of traceability both of inputs (e.g. animal feed) and of outputs (e.g. primary production, processing, storage, transport and retail sale). The EU has agreed standards to ensure food hygiene, animal health and welfare, and plant health and to control contamination from external substances, such as pesticides. Rigorous checks are carried out at every stage, and imports (e.g. meat) from outside the EU are required to meet the same standards and go through the same checks as food produced within the EU.