Twenty-first-century natural and deliberate catastrophic health events have demonstrated their potential to strain existing medical and public health systems’ capacities. Changing climates, the emergence of new diseases, globalization, and limited global health governance each has the potential to further challenge the delivery of public health and medical care in the coming decades. World leaders must now prepare for the threat of an influenza pandemic that could disrupt lives, devastate communities, and destroy economies. NATO has extensive experience in planning and conducting multinational operations and is uniquely positioned to guide nations’ pandemic preparedness efforts. From November 30, 2008, to December 8, 2008, the NATO Science for Peace and Security Program sponsored an Advanced Studies Institute in Milan, Italy, to help regional leaders to better prepare for pandemic threats. Over the course of two weeks, 60 participants from almost 20 countries collaborated and shared knowledge and training learned from current pandemic planning efforts. This paper attempts to summarize some of the major critical lessons from past catastrophes – lessons that are intended to inform future NATO pandemic preparedness efforts by member countries.