I’ve been investigating the new Microsoft UI Automation (MUIA) library over the past few months. MUIA is a large code library that helps you write UI test automation for Win32, .NET, and WPF applications. I’ve discovered there is quite a bit of good high-level documentation for MUIA available on the Internet, but currently there is almost no good "how-to", "nuts-and-bolts" information. I hope to remedy that with a series of blog entries and MSDN Magazine articles. The term "Microsoft UI Automation" is a bit fuzzy. More specifically the actual functionality of much of MUIA is contained in the System.Windows.Automation namespace (and others) of the .NET Framework. The functionality of this namespace is in turn contained in four DLL libraries, including a UIAutomationClient.dll which ships as part of the .NET 3.0 Framework. You can think of MUIA as a successor to the old Microsoft Active Accessibility (MSAA) library. MSAA was originally intended just for accessibility but was found to be useful for test automation. Microsoft UI Automation was designed from the outset for both accessibility and test automation. I believe that MUIA will quickly become the most widely-used method for Windows application UI test automation. The Microsoft UI Automation library is free, and because it ships with .NET 3.0 the library is a de facto standard.