Some farmers, and consultants, are better at their job than their colleagues. A branch of artificial intelligence known as expert systems attempts to capture this difference (their expertise) in computer based systems and make the skills available to all producers. This paper contains a review of the developments in this area as well as a discussion on the probable place of expert systems in farm management. It is concluded that expert systems are more likely to make a contribution to practical decision making than the many sophisticated models developed over the years but which are in fact seldom used by producers.