When medical care is initiated at a mass casualty event, the first activity is the triage of victims, which is the grouping by victims severity of injury. Paper triage tags are often used to mark victims' triage status and to record information on injuries and treatments administered in the field. In this paper we describe the design and development of an"Intelligent Triage Tag" (ITT), an electronic device to coordinate patient field care. ITTs combine the basic functionality of a paper triage tag with sensors, nonvolatile memory, a microprocessor and 802.11 wireless transmission capabilities. ITTs not only display victims' triage status but also signal alerts, and mark patients for transport or immediate medical attention. ITTs record medical data for later access offsite and help organize care by relaying information on the location of the victims during field treatment. ITTs are a part of the Wireless Information System for Medical Response in Disasters (WIISARD) architecture.