An incident response team or emergency response team (ERT) is a group of people who prepare for and respond to any emergency incident, such as a natural disaster or an interruption of business operations. Incident response teams are common in public service organizations as well as in organizations. This team is generally composed of specific members designated before an incident occurs, although under certain circumstances the team may be an ad hoc group of willing volunteers.
Incident response team members ideally are trained and prepared to fulfill the roles required by the specific situation (for example, to serve as incident commander in the event of a large-scale public emergency).
As the size of an incident grows, and as more resources are drawn into the event, the command of the situation may shift through several phases. In a small-scale event, usually only a volunteer or ad hoc team may respond. In events, both large and small, both specific member and ad hoc teams may work jointly in a unified command system.
Individual team members can be trained in various aspects of the response, either be it medical assistance/first aid, hazardous material spills, hostage situations, information systems attacks or disaster relief. Ideally the team has already defined a protocol or set of actions to perform to mitigate the negative effects of the incident.