@AshokO07 A RobotActivity is triggered by your Pega Platform application (usually within a case). An Activity is what you’d use for an attended automation not triggered by your Pega Platform application. Activities are queued, so as long as you call Start or StartActivity for Activity 2 off of your ActivityCompleted event for Activity 1, then Activity 1 will wrap up and allow Activity 2 to start and complete. If you tried to perform a StartAndWait, then it would never allow Activity 1 to fully finish, so it would always time out. You just need to be aware that all threads of Activity 1 must complete before Activity 2 will start.