The Open Access Scholarly Information Sourcebook (OASIS) has been launched at the 13th International Conference on Electronic Publishing (ELPUB2009), which took place in Milan, Italy from June 10-12. OASIS aims to provide an authoritative ‘sourcebook’ on Open Access, covering the concept, principles, advantages, approaches and means to achieving it. The site highlights developments and initiatives from around the world, with links to diverse additional resources and case studies.