In our project we have multiple (seven) configurations for various environments – development, nightly build server, test env. 1, test env. 2, test env. 3, … . For all these environments whe have transformations based on MS Xml Document Transformation. These transformation can be run automatically by VS during deployment or you can use extension SlowCheetah and define transformations in your MSBuild. But this was not suitable for us. We are often switching between environments during the development, so we need to change configuration quickly – for example, just right+click on the transofmation file and run it. There was no existing solution providing these abilities. For this purpose I have created a VS extension ConfigTransfomation. You can specify various transformation files for one configuration file (and you don’t have to create a build definition for them!). Just right-click on it and see the thre preview of the transformation or run it.