[Richard Flynn]

You can set up a 'Waiting For' context, and then just put that action into the new Context. You can also use the Context inspector on your new context to uncheck 'Allows next actions'—that then means that any action in that context is never 'available' to be done by you. However, you can easily set up a perspective to look at your Waiting For context for a plain list of everything you're (er) waiting for.