The Hospital Emergency Incident Command System (HEICS), now in its third edition, has emerged as a popular incident command system model for hospital emergency response in the United States and other countries. Since the inception of the HEICS in 1991, several events have transformed the requirements of hospital emergency management, including the 1995 Tokyo Subway sarin attack, the 2001 US anthrax letter attacks, and the 2003 Severe Acute Respiratory Syndrome (SARS) outbreaks in eastern Asia and Toronto, Canada. Several modifications of the HEICS are suggested to match the needs of hospital emergency management today, including: (1) an Incident Consultant in the Administrative Section of the HEICS to provide expert advice directly to the Incident Commander in chemical, biological, radiological, nuclear (CBRN) emergencies as needed, as well as consultation on mental health needs; (2) new unit leaders in the Operations Section to coordinate the management of contaminated or infectious patients in CBRN emergencies; (3) new unit leaders in the Operations Section to coordinate mental health support for patients, guests, healthcare workers, volunteers, and dependents in terrorism-related emergencies or events that produce significant mental health needs; (4) a new Decedent/Expectant Unit Leader in the Operations Section to coordinate the management of both types of patients together; and (5) a new Information Technology Unit Leader in the Logistics Section to coordinate the management of information technology and systems. New uses of the HEICS in hospital emergency management also are recommended, including: (1) the adoption of the HEICS as the conceptual framework for organizing all phases of hospital emergency management, including mitigation, preparedness, response, and recovery; and (2) the application of the HEICS not only to healthcare facilities, but also to healthcare systems. Finally, three levels of healthcare worker competencies in the HEICS are suggested: (1) basic understanding of the HEICS for all hospital healthcare workers; (2) advanced understanding and proficiency in the HEICS for hospital healthcare workers likely to assume leadership roles in hospital emergency response; and (3) special proficiency in constituting the HEICS ad hoc from existing healthcare workers in resource-deficient settings. The HEICS should be viewed as a work in progress that will mature as additional challenges arise and as hospitals gain further experience with its use.