The Gateway Certification Guide (GCG) is designed to assist Australian Government agencies and service providers wishing to pursue certification, including recertification. The Gateway Certification process provides an independent assessment that an Australian Government agency or service provider's gateway has been configured and managed appropriately and that suitable safeguards have been implemented and are operating effectively. This assurance will give clients using the gateway a level of trust in the service provided. The document also provides guidance and ideas to agencies considering secure gateway design, development or management issues, and can provide a reference for independent verification of any gateway. Version 3.0 of the Gateway Certification Guide was published in March 2004. This version was written to account for modified policy and guidance in the newly released Australian Government Information Technology Security Manual (also known as ACSI 33). The GCG homepage is located at: http://www.dsd.gov.au/library/infosec/gateway.html