The intricate and multifaceted nature of the Information Technology Infrastructure Library (ITIL) means that it is best organised and reviewed not as one whole qualification, but as two separate streams – Lifecycle and Capability. 

The Lifecycle stream is broken down further into five modules, built around the core ITIL volumes, which address the entire lifecycle of an IT service. Meanwhile, the Capability stream focuses more on process activities such as operational support and analysis, and service offerings and agreements.

For now, let's direct our attention towards the five ITIL Lifecycle stream modules, and break them down so that you can understand the key components of ITIL. 

ITIL Lifecycle: Service Strategy

The first module in this stream starts at the beginning of an IT service lifecycle – with the process of understanding organisational objectives and customer needs.

This module essential involves defining your new IT service and identifying the market space you are targeting. It also encompasses the process of conducting strategic assessments, managing finances and consumer demand, and identifying critical success factors and potential risks.

ITIL Lifecycle: Service Design

Next we cover the concept of service management, and the purpose and objectives of effective service design, from a bigger picture perspective as opposed to the day to day operational details. 

ITIL Lifecycle: Service Transition

Service transition addresses the problems and pitfalls of introducing and developing new IT services into existing environments, and focuses on how this process can be improved and streamlined. 

ITIL Lifecycle: Service Operation

Moving forward, the next certification in the ITIL Lifecycle stream addresses service operation – the actual process of ensuring that all ITIL based IT services are delivered in a productive, effective and efficient manner. 

This is arguably one of the most critical components of the ITIL Lifecycle as it focuses on the day to day operations and the delivery of business value. However, in order to be truly effective, this module should be considered as part of the larger ITIL framework. 

ITIL Lifecycle: Continual Service Improvement

The ITIL Lifecycle stream concludes with an examination of how to achieve continual incremental and large-scale service improvements. This forward-thinking module is essential for CIOs, CTOs and other IT decision makers looking to maximise the potential of new IT services.