Microsoft's position on virtualization of Exchange Server has evolved from a flat "no, you can't," and customers of all sizes have embraced virtualization in the hopes of cutting costs and increasing reliability and flexibility. At the same time, Microsoft has engineered Exchange 2013 for their own cloud offering, Office 365, which runs exclusively on physical hardware. To be sure that you’re getting the best value for your deployment investment, you need to understand how Exchange servers can be virtualized, the pros and cons of implementing Exchange in your own private cloud, what storage and reliability pitfalls you need to avoid, and how to best take advantage of modern virtualization and storage technologies.