We need a PC having Windows Vista/7/2008/2008R2. We can also use Windows XP, but it is not recommended. .NET Framework 4.0 is a must. Once we install .NET Framework 4.0, we can run workflow applications. To develop WF4 workflow applications, we should also have Visual Studio 2010 installed on our computer. To host WF4 as a WCF service in IIS, we should install IIS7/7.5 in our computer.