The July 2010 revision to the National Health Data Dictionary (NHDD) including national minimum data sets (NMDS) has now been released and is available on the Australian Institute of Health and Welfare (AIHW) website. As part of the METeOR metadata online registry, the dictionary's purpose is to provide national standards on the health reporting framework for both statistical and clinical analysis which provides meaningful input to community discussion and public policy debate on health issues in Australia. The Dictionary is available online at http://meteor.aihw.gov.au. This version confirms to international standard ISO/IEC 11179 Information Technology Metadata Registries (MDR), 2003.