Sakai is an open source collaboration and learning environment. Sakai is part of the Apereo Foundation suite of open source tools for education.

Sakai is used in many ways, from traditional courses with online components (such as resource management and forum-based discussion) to more advanced online approaches (such as flipped classrooms and fully-online teaching). A special distinction of Sakai over other LMSes is its built-in support for dedicated project work sites, which allows organizations and project teams to coordinate project administration, share resources, schedule activities, develop collaborative work products and track progress towards completion. These project collaboration spaces are widely used by student groups, faculty committees, thesis committees, strategic planning teams, re-accreditation teams and others tasked with important projects beyond the classroom.

Sakai 21 introduces Dark Mode, the new Sakai Dashboard tool and enhancements to Lessons, LTI Advantage, Assignments, Gradebook, Rubrics, and more. Development goals for Sakai are to become more nimble, lighter, and more responsive as a product and as a community.