There is increasing demand these days for IT to publish a service catalog, thereby automating the service request process for end users. These service requests can include basic orders for hardware, software, account access, and badges, or may extend to requests for infrastructure changes such as commissioning a server or configuring a firewall. When it comes to meeting these demands, IT struggles with the question of where to begin. How are services defined? How do services differ from requests? How will a service provided by IT impact the business? Here’s some news for IT: the service catalog isn’t just your responsibility. Yes, the service catalog begins with you, defining the services IT will provide; however, representatives of the business need to be involved, working alongside IT in the development of service offerings that best serve the business.
When we ask IT people who their customers are, the answer we often get is that the customer is their internal IT support staff. Very seldom do we hear that it’s business. As a result, the Service Catalog is designed around IT-centric requests. Business users find it complex and difficult to navigate if they’re given access to it at all. To mitigate this complexity and to improve support for the business, Gartner recommends defining the IT Service Portfolio before starting a service catalog project. 
What is the “IT Service Portfolio?” It is a complete set of services provided by an IT service provider. It represents the IT providers’ commitments and investments to their business customer’s goals and objectives. Essentially, these are the services IT provides in order for the business to thrive and grow.
The Service Portfolio includes a) the services that are under development and haven’t been released yet, b) live services which are currently provided to customers, and c) those services that are to be retired and that are no longer needed to support the business. Within the Service Portfolio, the components of the service are defined. Requestable services can then be added to the business service, IT service, or both, as applicable.
So why is this important? The value of the Service Portfolio is in providing the structure for defining IT services for the service catalog that support the business and the organization’s customers. The service catalog provides detailed information about each request including fulfillment expectations. The service catalog should include a convenient, easy-to-navigate interface to assist customers in quickly selecting what they want and submitting their requests.
As the request moves through the fulfillment lifecycle, the end user is kept up to date on its progress. In some instances, the requester may be involved in answering technical questions or making decisions regarding their request. In addition, the IT organizations responsible for fulfilling the request are aware and prepared to proactively communicate with the requester.
Maintaining the service catalog and associated requestable services results in an easy-to-use, up-to-date, and requestable service catalog for your customers. By providing an open channel of communication and a documented fulfillment process, the request is fulfilled in a predictable manner resulting in a very satisfied customer.
 Critical Capabilities for IT Service Catalog Tools, Gartner, March 17, 2014