The International Standards Organisation (ISO) decided to formalise the composition of quality systems in order to have a uniform approach, so that the concept of a quality system means the same thing to everybody. Thus ISO developed a set of standards for quality systems that outline the operating procedures for various types of businesses. Hence, ISO standard 9000 was then produced as a guide for the manufacturing industry.

The ISO 9000 is a guide to the use of standards 9001 to 9003. ISO 9001 is the most comprehensive standard and aims to cover the design/development, production, installation and servicing functions of a business. Thus for an organisation wanting to implement a quality system to cover all these functional areas, the ISO 9001 standard is appropriate.

Amongst the ISO 9000 series standards, ISO 9001 is the most comprehensive. It contains 20 main items, known as the Quality System Requirements, each one of which is further subdivided as outlined below:

1. Management Responsibility
2. Quality System
3. Contract Review
4. Design Control
5. Document Control
6. Purchasing
7. Purchaser Suppled Product
8. Product Identification and Traceability
9. Process Control
10. Inspection and Testing
11. Inspection, Measuring, and Test Equipment
12. Inspection and TEst Status
13. Control of Nonconforming Product
14. Corrective Action
15. Handling, Storage, Packaging, and Delivery
16. Quality Records
17. Internal Quality Audits
18. Training
19. Servicing
20. Statistical Techniques

The main purpose of the ISO standards is to ensure that the procedures and practices required for guaranteed product quality are in place. When a contractual arrangement is entered into, it is important for the client to feel confident about the supplier's ability to meet the agreed targets. In essence, any organisation's claim regarding the existence of a quality systems or conformance to appropriate ISO 9000 series standards needs to be confirmed. The accreditation process serves this purpose.