Established criteria against which performance in terms of meeting customer requirements is assessed. Nationally and internationally recognised quality standards include: BS 5750 – the British standard on quality management systems; EN 29000 – the European standard; and ISO 9001 – the International standard. To achieve BS 5750, EN 29000 or ISO 9001 certification an organisation must essentially document, implement and maintain a quality management system, and continually improve its effectiveness in accordance with the requirements laid down by the relevant quality standard. The emphasis is not on checking the standard of the product, but on ensuring that the organisation has developed and then documented the procedures to be followed to ensure a quality product. These quality standards are reviewed every five years.