Many State legislatures and health departments have amended State statutes and regulations to reflect modern principles of public health emergency preparedness based, in part, on the Model State Emergency Health Powers Act (MSEHPA) drafted in fall of 2001 by the Center for Law and the Public's Health at Georgetown University and The Johns Hopkins University.8 MSEHPA presents State and local governments with a template for reviewing existing emergency declaration laws and developing legislative or other regulatory reforms to facilitate an effective public health response.9 While this chapter refers to MSEHPA to explain common provisions that are featured in many States emergency preparedness laws, MSEHPA is not law unless a State has enacted it. According to the Center, more than 35 States have enacted laws based in whole or part on MSEHPA since the Act's completion.10 These laws vary across jurisdictions and may be interpreted differently depending on a host of factors. (AHRQ, Mass Medical Care, 2007, p. 27)