I have a WF which will be hosted on WCF . The service Contract will contain a single operation containing two parameters. Parameter1 will be a string and will contain the name of the workflow to invoke and parameter two will contain the input for the invoked Work Flow. All operations will take the same parameter. All the operations will return the same return value. I have created the service implementation and I would like to depending on the value of parameter1 start executing the appropriate workflow and return the value (There can be number of workflow classes say Operation1, Operation2...which will be the passed in as the value in Parameter1). How can I instantiate different workflow classes and pass parameters and get the return values from them which I should then pass back to the calling Client. (Also Should I be using ReceiveActivities in all of my Launchable WorkFlow Classes ? ) Any code samples or pointers would help