The 4 fundamental pillars are
- Responsibility, i.e., it should be clear who is responsible for what.
- Traceability, ensured by logging all activities.
- Repeatability, ensured by documenting the work processes.
- continuous process improvement, done by evaluating the processes regularly.
A common misconception about ISO 900x is that it has to do with the quality of the final product. This is the ultimate goal, however the ISO standard is primarily focused on the processes used to produce the product. It is quite easy to have a ISO 9001 certified company that produces rubbish, so long that all processes are documented and logged, and the delegation of responsibility is clear :)
It was a surprise to find out how short the ISO 9001:2000 standard actually was, only 19 pages in the format I have it!