Abstract: The aim of IPAWS (Integrated Public Alert and Warning System) is to alert and warn the American people as much as possible in situations of war, terrorist attack, natural disaster, or other hazards with multiple medias. As a “system of systems” IPAWS evolves Emergency Alert System (EAS), National Warning System (NAWAS), AMBER Alert, NOAA Weather Radio, Radiological Programs Chemical Stockpile and Web Alert & Relay Network (WARN) and so on. IPAWS conceptual architecture includes three parts: alert and warning inlet from federal, State and local governments, alert aggregation and outlet of multiple media. Its expected objective, alert effect and practicability are limited. To learn the lessons of IPAWS, China should plan and establish a Public Alert and Warning System to suit Chinese situation. A system consisted of points, bread and wet is suggested.