This document summarizes three cases of organizations migrating to open source software in Japan. The first case was a town hall that migrated to StarSuite on SunRay terminals and OpenOffice.org on Windows servers and PCs. The second case was a town hall that migrated to OpenOffice.org on Linux PCs. The third case was a private company that migrated to OpenOffice.org on Windows PCs. The document also discusses reasons for the recent increase in migrations in Japan and movements within the Japanese government to support open source software.