Keeping an inventory of all software licenses is not just an exercise that helps organizations controlling software costs and adjusting future purchases, but it is a necessity for compliance requirements. A business may fail a software license audit and is asked to pay hefty sums, let alone the potential embarrassment if the news goes public! It is a good business practice to have an inventory of all software licenses used on the company's network, servers, desktops, laptops and mobile devices. Some software inventory tools provide additional functionality that helps IT staff resolve computer problems faster. For instance, when a user reports a problem to helpdesk support, the helpdesk personnel can inquire a software asset tool to verify the user's computer configuration rather than engaging in a long talk with the end user. Other functions may include software usage metering, software delivery and workflow automation.
To get an idea of a typical solution, I suggest you read this guide from ScriptLogic.