Geographic Information Systems (GIS) provide a range of techniques which allow ready access to data, and the opportunity to overlay graphical location-based information for ease of interpretation. They can be used to solve complex planning and management problems. All phases of emergency management (reduction, readiness, response and recovery) can benefit from GIS, including applications related to transportation systems, a critical element in managing effective lifelines in an emergency. This is particularly true immediately before and during a volcanic eruption. The potential for volcanic activity in New Zealand is high, with 10 volcanoes or volcanic centres (Auckland, Bay of Islands, Haroharo, Mayor Island, Ruapehu, Taranaki, Tarawera, Taupo, Tongariro (including Ngauruhoe) and White Island) recognised as active or potentially active. In addition there are many active and potentially active volcanoes along the Kermadec Island chain. There is a great deal of background information on all of these volcanoes, and GIS is currently being used for some aspects of monitoring (e.g. ERS and Envisat radar interferometry for observing deformation prior to eruptions). If an eruption is considered imminent, evacuation may be necessary, and hence transportation systems must be evaluated. Scenarios have been developed for many centres (e.g. Taranaki/Egmont and Bay of Plenty volcanoes), but so far the use of GIS in planning for evacuation is limited. This paper looks at the use of GIS, indicates how it is being used in emergency management, and suggests how it can be used in evacuation planning.