TaskCompletionSource for Task

There is no non-generic version. However, Task<T> derives from Task, so you can just use TaskCompletionSource<bool> and return the task.

Task SomeMethodAsync() { var tcs = new TaskCompletionSource<bool>(); // Implement method as needed return tcs.Task; // Return the Task<bool> as a Task } 

Note that I'm using bool just because it's a small value type, and the result will get "thrown away". Another option here is to make your own custom type and return that, ie:

private struct EmptyType {} Task SomeMethodAsync() { var tcs = new TaskCompletionSource<EmptyType>(); // Implement method as needed // Use tcs.SetResult(default(EmptyType)) or similar return tcs.Task; // Return the Task<bool> as a Task } 

The main advantage here is the type is the smallest possible (least waste), and a type that doesn't suggest there is a "value" contained within the result (if the consumer does use reflection, etc).