With 60% of corporate knowledge workers reporting that email remains their most commonly used mode of communication, email continues to be the backbone of enterprise communications and could be considered the most critical infrastructure for daily operations.1 Cloud-delivered email services are rapidly becoming the preferred implementation approach by IT organizations. With over 155 million users already running on Office 365,2 organizations are realizing significant benefits over on-prem solutions, including reduced management costs, regulatory compliance, and the accounting shift from CapEx to OpEx.