The DFSMShsm control data sets contain information describing the status of the DFSMShsm managed data sets and volumes. Each control data set requires regular maintenance (backup and reorganization) and auditing to ensure the integrity of the data managed by DFSMShsm. The DFSMShsm product provides the AUDIT command to detect, report, diagnose, and often provide automated correction for discrepancies between the control data set, ICF user catalog, and DFSMShsm owned volumes. Mainstar: FastAudit family of products provides the same audit capabilities as with the DFSMShsm AUDIT command, but at faster speeds. Using the FastAudit products, the audits are comprehensive (perform multiple audits with one command), flexible, and easy to use. Audits of some, or all of the z/OS and OS/390 metadata environments can now be done frequently, even daily, to identify and resolve errors before they lead to data loss or failed access. This IBM Redbook outlines the tasks to use DFSMShsm Audit and the use of Mainstar's FastAudit program to manage your HSM environment.