After a period of relative calm in the first half of the 2000s, the South China Sea dispute is back in the headlines. A long-running dispute, the South China Sea is now challenging regional relations in ways that it has not before. While the zero-sum nature of competing legal claims and perceived nationalist affronts associated with territorial disputes make them as a general category more challenging for those involved, the South China Sea can also be characterized as especially complex and difficult. The cast of claimants is large and varied (six in all: China, Taiwan, Malaysia, the Philippines, Vietnam and Brunei--with Taiwan a non-state entity); (1) the legal bases for claims are mixed; the economic stakes are great. Home to some of the busiest sea lanes in the world, more than a quarter of the world's trade pass through the South China Sea each year. Upwards of 80 and 90 per cent of Chinese and Japanese oil imports also traverse through these waters. A rich fishing ground, the South China Sea is also an important resource for the local and national economies of the states involved. This is to say nothing of the potential hydrocarbon resources these waters are speculated to offer in an age of growing resource demand and scarcity.(2) All these factors have long complicated states' ability to resolve the dispute, but since 2008 the frequency of troubling confrontations between China and the other claimants has increased, as each tries to stake, defend and expand their physical claims via a range of activities. Of note have been efforts by China to detain and "expel" Vietnamese and Philippine fishermen from disputed waters. Most serious have been a number of high-profile exchanges (both diplomatic and naval) between China, the region's rising power, and the United States, the region's status quo power, over maritime rights. Such exchanges have elevated the dispute to a different level of geopolitical attention. While assessments about the likelihood of serious conflict vary, the historical characterization of these waters as being "dangerous ground" (3) may be truer today than it has ever been in the past. The articles in this special issue on the South China Sea offer different perspectives on recent developments. Three of the articles (Goldstein, Thayer and Womack) were originally presented at the 2011 International Studies Association's annual conference in Montreal, where the panel was the subject of lively and engaged discussion. Originally, the panel also included Peter Dutton, whose paper was published elsewhere in the interim. (4) Though we were sorry to lose Peter, we were fortunate to bring Taylor Fravel onboard in his place. This introduction serves to draw out some common themes and challenges highlighted by the authors and their implications for future developments. In particular, it highlights the various conflicts and tensions that have come to be intertwined with the South China Sea, pushing it to the foreground: conflicts over not just territory but also maritime rights and jurisdiction, resources, and increasingly, the relative influence of China and the United States as the region's (and world's) rising and status quo powers. It is the conclusion of the authors that mismanagement for all concerned, including non-claimants like the United States, will carry high--even unacceptable--costs.