In this paper we report on a study to examine the usefulness of the MLD (Multi-Layered Display) as a device for creating physically distinct but visually overlapping information, what we refer to as 'information layering'. The technique was applied to emergency ambulance control, as a method for reducing visual clutter and information complexity in displays used by controllers. The results of the study show that participants completing simulated dispatch tasks in the MLD condition performed better on all categories of task difficulty compared to participants using a standard single layer display. However the improvements in performance were not significantly different
