The five stages of the ITIL life cycle

The five service life cycle stages are central to defining the overall ITIL life cycle. You can see these stages, in their cyclical context, in Figure 4.2. Here, you can see the five stages arranged in a logical structure, with interconnected processes and functions in each stage connecting them to each other.

At the center is Service Strategy. This service "ring" is itself then surrounded by a connected circular flow of three elements: Service Design, Service Transition, and Service Operations. Then, enwrapping the entire structure is Continual Service Improvement.

This service life cycle concept is most relevant to people like us who are invested in software. We will therefore tend to identify with the Service Operations stage. Under this stage, the most relevant function is known as the Application Management function.

The Service Operations stage is particularly relevant to us in software because the Application Management function is responsible for the following three elements:

• Managing software applications throughout their lifespan, even up to their eventual decommissioning
• Supporting, maintaining, and improving operational software applications
• Helping to design, develop, and deploy software applications

As you can see, the responsibilities of the Application Management function are wide-ranging, and go so far as to include elements of design and development work.