- Free Software Foundation and GNU Project - Non-profit organization dedicated to eliminating restrictions on copying, redistributing, understanding, and modifying computer programs. GNU Project was begun to develop a complete free Unix-like operating system.
- Free Software Foundation Europe - European branch of the FSF. Includes news and events listings, press information, and a document archive.
- Jabber Software Foundation - Not-for-profit organization that oversees the general development of XMPP and maintains the Jabber Enhancement Proposals.
- Open Invention Network - An intellectual property company that was formed to promote Linux. It acquires patents and makes them available royalty-free to any company, institution or individual that agrees not to assert its patents against the Linux System.
- Open Solutions Alliance - A nonprofit, vendor-neutral consortium dedicated to driving the adoption of comprehensive open source business solutions.
- Open Source Academy - UK government portal which aims to encourage the use of Open Source Software by local authoritie. Offers opportunities for knowledge sharing and practical advice.
- Open Source Advisory Service - Promotes awareness and understanding of the legal, social, technical and economic issues that arise when educational institutions engage with free and open source software. News, publications, events, and FAQ.
- Open Source Initiative - Dedicated to managing and promoting the Open Source trademark for the good of the community. Includes a definition of 'Open Source', and a list of approved licenses.
- Open Source Resource Center - Project of the Pakistan Software Export Board. Includes news, details of strategy, aims and services, discussion forums, and events listings.
- Open TTT - A European Union funded project that aims to facilitate transnational technology transfers and open source partnerships for enterprises and network of developers.
- OpenForum Europe - Not-for-profit organisation helping to accelerate, broaden and strengthen the use of OSS in business and government. News and events, information about OSS, and articles.
- Python Software Foundation - Non-profit organization devoted to advancing open source technology related to the Python programming language. Provides membership information, missions statement, and details of how to get involved.
- Software in the Public Interest, Inc. - Aims to help organizations develop and distribute open hardware and software. Includes news, details of supported projects, and membership details.
- The Apache Software Foundation - Supports the development of a number of open-source software projects, including the apache webserver. Includes license information, latest news, and project sites.
- The Linux Foundation - A non-profit consortium dedicated to fostering the growth of Linux, and promoting standardization and technical collaboration. Provides details of activities and working groups, a collaboration forum, and developer services.
- Xiph.org Foundation - Non-profit corporation dedicated to protecting multimedia from control by private interests, by developing free and open protocols and software. Information about the foundation and its current projects.
- XMPP Standards Foundation - Contact info, architectural docs and a weblog on Extensible Messaging and Presence Protocol (XMPP), an open XML communications technology.
