Official statistics can be disseminated via different media including the Internet, paper publications, CDROM,fax, public speeches, and press releases. Dissemination formats such as HTML pages, PDF documents, and Excel sheets are widely used by national and international statistics agencies in releasing their data. However, with the recent worldwide movement that calls for opening up government or public data, more governments and institutions are increasingly publishing their data in more open formats such as SDMX, CSV, XML that allow users to freely use and reuse or even link their data. Examination of dissemination formats of statistics of the AEC countries in this study has shown that data still need to be disseminated in a more open format in cases of national statistical organizations in Thailand, Cambodia, Laos, and Myanmar, as well as ASEAN.