Lifelines are systems and facilities that provide critical services vital to the function of a community and important to the emergency response and recovery after a natural disaster. Lifelines include communication, electric power, liquid fuel, natural gas, transportation (airports, highways, ports, rail and transit), water, and wastewater.

The purpose of this guide is to direct users to authoritative information sources for research, including existing professional organizations, to advance the study of lifeline hazard mitigation.