This paper describes use cases for the application of Trusted Computing Group (TCG) techniques and specifications to storage devices. The use cases fall into three broad categories: the trusted attachment of storage devices to their hosts, more general policy driven secure control over features of storage devices such as storage locations and storage encryption, and secure, session-oriented, messaging of such controls to storage devices. This document also describes the proposed T10 SCSI and T13 ATA commands that support these security communications to storage devices. The Use Cases provided in this document are a subset of the use cases developed by the Storage Workgroup that have been entirely re-written for this exposition for the sake of clarity. The specific terms used in this Use Case exposition may change in the actual specification as the terminology is vetted for consistency.