The document compares the messaging solutions Zimbra Collaboration Suite (ZCS) and Google Apps. It summarizes their features for enterprises and higher education institutions. ZCS is an open-source solution that provides email, calendar, contacts and collaboration features. It can be deployed both on-premise or hosted. Google Apps is focused on hosted deployment and utilizes advertising monetization. The document evaluates the solutions across categories like functionality, administration, deployment options, and privacy controls to help organizations evaluate which system best fits their needs. Representatives from Zimbra and a higher education IT department discuss their experiences with ZCS.