This workshop brought together researchers concerned with fundamental issues of modelling action, those developing automated planning techniques and those attempting to implement autonomous agents acting in the world. In the past, these research communities have been separate from each other to a surprising extent. Researchers interested in theories of action have busied themselves with finding solutions to the frame and ramification problems, for very expressive theories of action. On the other hand, researchers interested in developing planning systems have typically concentrated on efficiency over expressiveness and assumed away the frame and ramification problems by means of the “STRIPS assumption”. Finally, researchers interested in implementing autonomous agents have found their attention occupied by issues of execution monitoring and sensing.