In most cases, your code will not deal with System.Web.HttpWorkerRequest directly because request and response data are exposed through the System.Web.HttpRequest and System.Web.HttpResponse classes. Some internal ASP.NET classes extend this class. If your code implements its own hosting environment, it will need to extend this class to call the HttpRuntime.ProcessRequest(HttpWorkerRequest) method. In addition, your code could create a derived class for the purpose of child-request execution within a given application in order to pass its instance to HttpRuntime.ProcessRequest(HttpWorkerRequest). In this case, the derived class should keep a reference to the current System.Web.HttpWorkerRequest and delegate most of the methods to it.