Add reference to - System.Workflow.Activities - System.Workflow.Runtime - System.Workflow.ComponentModel - <the MyWorkflow assembly> in the WinForm codes, add member variable WorkflowRuntime myWorkflowRuntime = new WorkflowRuntime() Then, in the constructor of the winform. //setup event handler myWorkflowRuntime.WorkflowCompleted += new EventHandler<WorkflowCompletedEventArg>(wr_WFCompleted); myWorkflowRuntime.WorkflowTerminated += new EventHandler<WorkflowTerminatedEventArg>(wr_WFTerminated); //handler for the workflow thread. void wr_WFCompleted(object sender, WorkflowCompletedEventArg e) { MessageBox.Show("Workflow output" + e.OutputParameters["Field"].ToString()); } //to kick start the work flow thread. Type type = typeof(MyNamespace.MyWorkflow); //to pass parameter to the workflow thread. Dictionary<string, object> param = Dictionary<string, object>; param.Add("Field", System.Convert.ToInt32(123)); WorkflowInst...