Emergency management is the generic name of an interdisciplinary field dealing with the strategic organizational management processes used to protect critical assets of an organization from hazard risks that can cause disasters or catastrophes, and to ensure the continuance of the organization within their planned lifetime. Assets are categorized as either living things, non-living things, cultural or economic. Hazards are categorized by their cause, either natural or human-made. The entire strategic management process is divided into four fields to aid in identification of the processes. The four fields normally deal with risk reduction, preparing resources to respond to the hazard, responding to the actual damage caused by the hazard and limiting further damage (e.g., emergency evacuation, quarantine, mass decontamination, etc.), and returning as close as possible to the state before the hazard incident. The field occurs in both the public and private sector, sharing the same processes, but with different focuses. Emergency Management is a strategic process, and not a tactical process, thus it usually resides at the Executive level in an organization. It normally has no direct power, but serves as an advisory or coordinating function to ensure that all parts of an organization are focused on the common goal. Effective Emergency Management relies on a thorough integration of emergency plans at all levels of the organization, and an understanding that the lowest levels of the organization are responsible for managing the emergency and getting additional resources and assistance from the upper levels.