Health"Insite" is the Australian Government's Internet gateway to reliable health information online, providing access to over 15,000 information items on the websites of more than 80 approved information partners. The gateway provides a variety of searching and browsing options to assist users to find information on a wide range of health topics. It relies heavily on subject and other metadata associated with each information resource to provide relevance-ranked search results lists. Subject metadata terms are selected from the "Health and Ageing Thesaurus" which was developed by the Department of Health and Ageing Library. All of the Health"Insite" search and browse options have been successively improved over the eight years since Health"Insite" was launched, but the need for significant enhancements to the search engine and search results displays prompted a major upgrade. The upgrade also presents an opportunity to better integrate the "Health and Ageing Thesaurus" into the search engine to provide support for topic page authoring and searches on non-preferred terms, synonyms and related terms.