As my company continues to move enterprise applications to the cloud, the latest development presents a security opportunity. We are giving up our on-premises Microsoft Exchange email in favor of the Microsoft Office 365 service. With the transition, we might be able to curtail the common employee practice of communicating and storing sensitive business-related data in email.
I am encouraging the IT organization to tighten security by implementing controls that were either not available in our on-premises deployment or never implemented. The first order of business is a cleanup of accounts and distribution lists. We have hundreds of email-enabled distribution lists, and too many of them are available to the world. We should be able to cut down the number of lists and set rules about who can use them.
from Computerworld Cloud Computing http://www.computerworld.com/article/3194713/security/email-email-in-the-cloud.html#tk.rss_cloudcomputing