Headquarters: Redmond, Wash.
Revenue in Most Recent Quarter: $15.1 billion (Q1, FY2009)
Channel Chief: Allison Watson, corporate vice president, Worldwide Partner Group
Why It's a Strategic Storage Partner: Microsoft, with the release a couple years ago of its iSCSI target in its Windows operating system, lit the fire under what has since become the fastest-growing part of the storage market. Versions of Windows run many of the market's storage appliances, especially NAS appliances. And Microsoft, taking a page from VMware, is pushing hard into server virtualization, which is currently one of the top drivers for storage networks.