Loss of area freedom from invasive alien species can have serious food security implications and place huge responsibility on incursion response managers. They make critical decisions despite profound uncertainty surrounding invasion ecology, surveillance and control technology effectiveness and human behaviour. We propose a spatially-explicit model that can aid response managers in devising and testing management strategies in a virtual world where the costs of failure are negligible. We apply the model in a group-based decision setting in which participants practise responding to fictional disease incursions in a pome fruit production area in Australia. Using the model, the response management group was able to develop mutually satisfactory rules of thumb for the use of quarantine and destruction zones and for when to withdraw resources from eradication efforts. © 2015, Springer Science+Business Media Dordrecht and International Society for Plant Pathology.