The present invention extends to methods, systems, and computer program products for marshaling results of nested tasks. Unwrap methods are used to reduce the level of task nesting and insure that appropriate results are marshaled between tasks. A proxy task is used to represent the aggregate asynchronous operation of a wrapping task and a wrapped task. The proxy task has a completion state that is at least indicative of the completion state of the aggregate asynchronous operation. The completion state of the aggregate asynchronous operation is determined and set from one or more of the completion state of the wrapping task and the wrapped task. The completion state of the proxy task can be conveyed to calling logic to indicate the completion state of the aggregate asynchronous operation to the calling logic.