Consider a journal editor who has sent a submitted paper to a referee for comments that do not arrive by the expected date. This case illustrates the sort of “contigency,” or unexpected event, commonly occurring in routine office work that can be handled, the author argues, by a plan- based system capable of using domain-dependent knowledge to decide what to do next. Decisions take the form of condition-action pairs, such as

If failure is “referee forgot about paper” and “comments will be needed soon” then achieve goal “have referee reminded about paper.”

Araya mentions an experimental implementation of this contingency-handling process but gives no details. In the absence of a working system, evaluation of his model would be premature.