Headquarters: Redmond, Wash.
Revenue in Most Recent Quarter: $15.84 billion (Q4, 2008)
Channel Chief: Allison Watson, corporate vice president, Worldwide Partner Group
Why It's a Strategic Security Partner: Given that so many security attacks are aimed at or come through the desktop, it's no wonder that the world's most dominant desktop operating system vendor is a key security player for many solution providers. Patch Tuesday has become a holiday of sorts, the one day every month when solution providers and IT professionals the world over know they're about to get their hands on the latest Microsoft security patches. Microsoft builds a variety of security-minded features into Windows and also boasts its own Microsoft Security Response Center, a research group that aims to identify and respond to Microsoft software security vulnerabilities. A whopping 40.88 percent of solution providers who identified a vendor as strategic selected Microsoft.