In my ITIL v3 Foundation classes, students new to the terminology of formal IT service management often struggle to wrap their arms around the concept of the Service Catalog. Most IT staff can understand a category tree or a category-type-item schema. They look at the services they support from an IT point of view. But when IT needs to communicate to their customers, it’s important that the Service Catalog also have a business face. And IT should understand which external facing services are impacted by the business services they support.

For example, I buy books from Amazon.com. Books and the shipping that sends those books to my door are the services I buy from the business. The business in turn depends on order fulfillment and tracking systems, among others, to ensure accurate and timely delivery for me. In this example, “books” and “delivery” are the external services, which link to “fulfillment” and “tracking” systems in the Business Service Catalog. Those systems in turn link to “database”, “server” and “network infrastructure” in the IT Service Catalog.

It’s important that items in the Service Catalog be defined in simple terms with accompanying detailed descriptions so that the service definitions are widely understood. According to ITIL, the Service Catalog should define:

Of note here is the reference to supported services. Most services or systems, for example, will require network infrastructure. One challenging aspect of defining the service catalog is defining and recording the dependencies and relationships among services and components or configuration items (CIs). This is also, however, an exercise that offers great returns and benefits to the IT organization. If IT can identify relationships among services and CIs, then they can make more informed decisions when planning service outages and changes to the infrastructure.