by Rick Anderson This tutorial will teach you the basics of building an asynchronous ASP.NET MVC Web application using Visual Studio Express 2012 for Web, which is a free version of Microsoft Visual Studio. You can also use Visual Studio 2012. A complete sample is provided for this tutorial on github https://github.com/RickAndMSFT/Async-ASP.NET/ The ASP.NET MVC 4 Controller class in combination .N