There is a matrix that can be drawn, of the technology silos that IT manages on one axis mapped against the services that technology delivers to the business on the perpendicular axis. Service Management is about turning the IT department around 90° so they look at the services they provide to the business instead of looking at their technology.
That is to say, service management is about getting IT people (or in fact any provider of a service) to think first about what matters to the user of the service and only then derive from that what is required of the technology and systems that provide the service.
The cultural shift from product to service has left IT behind in large organisations. They have been split off as a separate tribe with their own language and culture while the business has moved on and expectations have changed. Drawing on the advanced ideas of the Manufacturing sector, Service Management has grown up within IT (hence the common term ITSM) in an attempt to heal the rift and bring corporate computing into the new age. We are just seeing a new development now where IT is taking Service Management to the business as an effective methodology for introducing customer-centric culture and processes across the organisation.
As a result of this shift in perspective, a second change results. Service management forces an organisation to think and structure itself around the services it delivers and hence the processes delivering those services, instead of around internal functions or technologies. For example, people are no longer labelled as the networks guy or the security person. They are the financials support person or the operations person instead.
Finally, a third change results from starting with business strategy: it gets people thinking about strategy.
Once we understand what services we provide and what the users need from those services, we can plan, spend, operate, measure and improve on that basis. This is a very powerful concept that has widespread applications, and we will see much more of it in future.