The Alliance represents the content management systems (CMS) behind roughly 50% of all websites online today. The Open Website Alliance was founded to promote the choice of open-source software and facilitate collaboration between free and open-source web content management projects, furthering openness, trust, and quality.

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In addition to a promise of joint collaboration, the Open Website Alliance members adhere to the Open Web Manifesto. Originally pioneered by the Drupal Association, the manifesto is a commitment to the web as an empowering tool, built on freedom and decentralization: “Everyone in the world, regardless of background, identity, ability, wealth, or status, has a home on the open web as a user, creator, architect, and innovator. It requires participation: The open web is a shared resource and a shared responsibility, sustained by deliberate choice and collaborative effort.”