AbstractA computer model has been developed to address the problem of attaining the most cost-effective balance when providing perimeter security at any given prison. The generalized analysis of security of perimeters (GASP) model evaluates the cost and performance of different prison perimeters in terms of several measures. The modelling process takes account not only of the site-specific problems such as perimeter shape, but also of the policy input of trade-offs between the various output measures of cost and effectiveness. Goal-programming and multi-criteria decision-making techniques have been used.