ISO 9000 is a globally recognized quality standard for organizations.
While ISO 9000 addresses quality standards across the organization, there is still a requirement to adopt a more rigid framework to turn desires into reality.
Within the IT Department frameworks like the ITIL version 3, offers that rigidity.
So where ISO 9000 defines the requirement for quality in the organization it is ITIL that will provide the detail of what has to be done and by who for the IT department.
The connection between Service Management and ISO 9000 is very apparent in the development of the ISO 20000 standard (Service Management standard) and the Service Quality Management Foundation (SQMF) program developed by EXIN.
SQMF includes learning on both ISO 20000 and ISO 9000.