A facility for booting a virtual machine hosted on a host is described. In one example facility, the facility boots the virtual machine in accordance with a policy instance associated with the virtual machine. As part of the booting, the facility extracts information needed to complete the booting from a virtual trusted platform module associated with the virtual machine, the extraction based upon the policy instance associated with the virtual machine. At the completion of the booting, the facility copies contents of a policy instance associated with the host into the policy instance associated with the virtual machine.