ISO 9001:2008 - for Quality Management Systems - This standard is the "granddaddy" of global quality management system standards, and is designed to be used by any organization as the foundation for a QMS. It also serves as the basis for many other QMS standards. ISO 9001:2008 remains the most popular QMS standard by far around the world.

Read more about ISO 9000
Two major focus points
Requirement of ISO-9001:2008 (In detail)
Quality management principles
Does ISO 9000 certification pay?
ISO 9001:2008 QMS benefits