The US's total annual agricultural output amounts to trillions of dollars and annual agricultural exports amount to billions of dollars. Thus, applying effective biosecurity measures in agriculture could ensure economic security by protecting livestock and crops against natural or weaponized pathogens. The US Agricultural Bioterrorism Act of 2002 authorizes an agricultural select agent list that includes 24 dangerous animal pathogens and 9 dangerous crop pathogens. Not only do these natural pathogens threaten livestock and crops, several nations have pursued agricultural pathogens as part of their weapons programs. Although theUS government and International bodies have taken steps to monitor agricultural epidemics, local protection and responses are lacking throughout the world.  Most livestock in developing nations are not housed in secure containment facilities and are thus, prone to infection by local pathogens.  In developed nations, livestock, other than poultry, are housed outdoors and also subject to local pathogens.  Similarly, crops are subject to local pathogens, harmful pests, and soil and weather conditions throughout the world.  If an epidemic occurs, most nations are unable to effectively limit or eliminate the epidemic's spread.The Center for Science, Technology and Security Policy at AAAS will host this two-part briefing series on agriculture security and food defense.  The issues discussed will be relevant to international (and national) security, agriculture and human health.