Welcome employees
By prepopulating circles, admins can ensure new employees are welcomed into Google+ with relevant and interesting content by colleagues and leadership. It also makes it easy for employees to send posts to, or start Hangouts with, specific teams.
Connect the company
Companies can develop apps that connect Google+ to internal systems, and ISVs can develop their own tools to interact with Google+ features such as posts, comments, and circles. Admins can also automatically post company-wide updates or announcements and manage circle membership for domain users.