The Open Source Initiative (OSI) is an American nonprofit organization that maintains The Open Source Definition (OSD), the predominant standard for open-source software. The organization was founded in February 1998 by Bruce Perens and Eric S. Raymond, part of a group inspired by the Netscape Communications Corporation publishing the source code for its flagship Netscape Communicator product. Later, in August 1998, the organization added a board of directors.
For most of its existence, the OSI's activities have been focused on the definition and certifying software licenses as compliant with it. OSI originally had a closed organizational model, but began to switch towards a membership organization in the 2010s to raise more money and expand its activities.