"Open Access" means free availability on the Internet of scientific or academic literature (mainly the peer-reviewed articles), allowing any user to read, download, copy, distribute, print, search, or link to the full texts.

Following the success of the previous conferences (held in May 2005, November 2006 and December 2008), the goal of this 4rd Open Access Conference is to foster the awareness, debate and sharing of experiences about Open Access.

The 4ª Conferência OA is part of a national project, the Open Access Cientific Repository and the main results will be presented at the conference.

The official languages of the 4rd Open Access Conference will be the Portuguese and English.