SOGo (formerly named Scalable OpenGroupware.org) is an open source collaborative software (groupware) server with a focus on simplicity and scalability. It is developed in Objective-C using PostgreSQL, Apache, and IMAP.

SOGo provides collaboration for Mozilla Thunderbird/Lightning, Microsoft Outlook, Apple iCal/iPhone and BlackBerry client users. Its features include the ability to share calendars, address books and e-mail using an open source, cross-platform environment. The Funambol middleware and the Funambol SOGo Connector allow SyncML clients to synchronize contacts, events and tasks.