1. A method for license management of virtual machines, comprising: receiving an event notification from a virtual machine manager operable to control the execution of one or more virtual machines, the event notification corresponding to a first virtual machine and indicating an event type associated with the first virtual machine; updating an inventory indicating a number of active instances of one or more applications based on the event notification; and determining compliance or non-compliance with one or more license policies based on the inventory, each license policy corresponding to at least one of the one or more applications.