Free access to knowledge is a central module within the context of Science 2.0. Rapid development within the area of Open Access underlines this fact and is a pathfinder for Science 2.0, especially since the October 2003 enactment of the “Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities”. Berlin Declaration on Open Access to Knowledge in the Sciences and Humanities (http://oa.mpg.de/files/2010/04/berlin_declaration.pdf)