AbstractPlanning the operations of a colliery in the medium term requires management to produce a statement of proposed layout of faces and deployment of men. A computer program was developed to calculate the outcome of implementing a particular plan at a hypothetical colliery. This formed the basis of a competitive syndicate exercise at the Staff College of the National Coal Board. The concept was then extended to real colliery planning, to allow planners and managers to consider a wider set of options than current manual methods permit. The paper describes the common approach and discusses the modifications that were necessary to achieve results quickly enough to influence colliery planning decisions.