The question arose at work the other day. I'll present my thoughts on the subject below.
The lifecycle perspective is really not entirelly new. Two ITIL version 2 books, Application Management and ICT Infrastructure Management, definatly had the lifecycle perspective although it was not applied to the service but to the application and the infrastructural components. What is new in version 3 is that it is applied to the IT Service. All 5 ITIL version 3 core books fit nicely in the new Service Lifecycle concept (see image).
Having said that does not mean I think there are necesarilly 5 stages in the Service Lifecycle. On the contrary. I would like to point out that the books should not be seen each as one of five stages.
It is clear when reading the books that Service Strategy (SS) is NOT a stage while Service Design (SD), Service Transition (ST) and Service Operation (SO) are. That is also clearly stated in the ITIL Glossary (v3.1.24). The glossary uses the term "stage" on SD, ST and SO. Here is a quote from the 3rd edition of the ITIL Refresh News on the subject:
"It [Service Strategy] also helps them make the business case for investments in the Lifecycle phases of Service Design, Service Transition, and Service Operation, and in the ongoing activity of Continual Service Improvement"
If not 5, then how many stages are there? Can we then state that there are 3 stages i the Service Lifecycle? Maybe not. The glossary state that Continual Service Improvement (CSI) is a stage in the lifecycle. I think this is not so strange considering that CSI is essential for the improvement of the service. Another aspect is that CSI is iterative in itself (PDCA, remember?) even if the SD, ST and SO should happen to be completely "linear". Something that has influenced the IT industry in general and the development of IT systems (and services) in particular is the iterative approach. The iterative approach is definitely in ITIL version 3 although I think it is not being used consistently in all aspects of the framework. One thing that the iterative approach does is that it weaves together SD, ST, SO and CSI. Improvement is done until the service is retired.
The difference between SS and the other books would be that SS preceeds the others and is answering the "Why?" more than the "How?". If we apply this on the Service Lifecycle it means that SS is the "base" for the others. Of course one could argue that the decision to "give life" to a service should be seen as part of that services lifecycle, but to me that is to much of a phylosophycal argument.
So the answer to the question as I see it is "No". Neither 3 or 5 but 4. 4 (SD, ST, SO and CSI) highly integrated iterative stages of a lifecycle that is the realisation of a strategy (SS).
What do you think?
I will return with more on version 3 and what I see as important, interesting or confusing in coming posts. Stay tuned.
Regards, David :-)
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