- [Openmeetings](https://openmeetings.apache.org/index.html) - Openmeetings provides video conferencing, instant messaging, white board, collaborative document editing and other groupware tools using API functions of the Red5 Streaming Server for Remoting and Streaming. ([Source Code](https://openmeetings.apache.org/scm.html)) `Apache-2.0``Java`
- [SOGo](https://sogo.nu/) - SOGo offers multiple ways to access the calendaring and messaging data. CalDAV, CardDAV, GroupDAV, as well as ActiveSync, including native Outlook compatibility and Web interface. ([Demo](https://demo.sogo.nu/SOGo/), [Source Code](https://github.com/inverse-inc/sogo)) `LGPL-2.1``Objective-C`
- [SuiteCRM](https://suitecrm.com) - The award-winning, enterprise-class open source CRM. ([Source Code](https://github.com/salesagility/SuiteCRM)) `AGPL-3.0``PHP`
- [Tracim](https://github.com/tracim/tracim) - Collaborative Platform for team collaboration: file,threads,notes,agenda,etc. `AGPL-3.0/LGPL-3.0/MIT``Python`
- [Zimbra Collaboration](https://www.zimbra.com/) - Email, calendar, collaboration server with Web interface and lots of integrations. ([Source Code](https://github.com/zimbra)) `GPL-2.0/CPAL-1.0``Java`