The Symposium on Avoiding Technology Surprise for Tomorrow's Warfighter is a forum for consumers and producers of scientific and technical intelligence to exchange perspectives on the potential sources of emerging or disruptive technologies and behaviors, with the goal of improving the Department of Defense's technological warning capability. This volume summarizes the key themes identified in the second and most recent symposium, a two-day event held in Suffolk, Virginia, on April 28 and 29, 2010. The symposium combined presentations highlighting cutting-edge technology topics with facilitated discourse among all participants. Three categories of surprise were identified: breakthroughs in product and process technology, new uses of existing technology, and the unexpectedly rapid progression of a technology to operational use. The incorporation of an adversary's own culture, history, beliefs, and value systems into analyses also emerged in discussions as an important factor in reducing surprise.