Procuring a service desk management system

In developing the IT department, implementing ITIL and creating information management structure, one early activity will be the buying of a service desk management system to support the service desk (the helpdesk). Such system are important because they help with customer service. They also provide a repository for the information about systems and software (configurations) customer and activities that the IT service department requires. Procurement of service desk software requires an understanding of the functional requirements and the selection of a system which suits the IT department.

Question: Define the main functions of a service desk system. Why is it so important in IT services? Critically compare three service desk support systems. Candidates include Marval Software, Hornbill, ServiceNow, IBM Tivioli, and HP's service desk software.

Explain what is meant by ITIL compliant. Provide some advice on how to select a service desk system. Consider whether you should implement ITIL processes and then get a new service desk system or put a new system in first to try to drive the adoption of ITIL processes.