ISO 20000 actually comprises two parts: ISO 20000-1 is the 'Specification for Service Management, whilst ISO 20000-2 is the 'Code of practice for Service Management'. The contents of these are as follows:

ISO 20000-1

Scope
Terms & definitions
Requirements for a management system
Planning and implementing service management
Planning and implementing new/changed services
Service delivery processes
Relationship processes
Resolution processes
Control processes
Release process

ISO 20000-2

Scope
Terms & definitions
The management systems
Planning and implementing service management
Service delivery processes
Relationship processes
Resolution processes
Control processes
Release management processes