OAPEN is dedicated to promoting Open Access publishing as an essential service to the academic community in the public interest. It provides a platform for the full-text dissemination of OA books and provides services to publishers as well as libraries. OAPEN builds a quality controlled collection of OA books, mainly in the area of humanities and social sciences. Participating publishers include Brill, Manchester University Press, Oxford University, Palgrave Macmillan, and many more.

The OAPEN Foundation is a non-profit foundation dedicated to OA publishing of academic books.