While the overall security situation in Southeast Asia is something of a mixed bag, with grounds for both optimism and pessimism, one of the most encouraging trends in recent years has been the development of ASEAN’s relations with major external powers. Relations between China and ASEAN in particular have demonstrated a marked improvement over the past decade, thanks to a combination of burgeoning economic ties, perceptions of China as a more constructive and responsible player in regional politics, and Beijing’s "charm offensive" toward Southeast Asia. Overall, the development of ASEAN-China relations poses few security challenges to the United States today: good relations between China and ASEAN enhance regional stability, and a stable Southeast Asia is clearly in America’s interests, especially with Washington focused on events in the Middle East. However, although ASEAN-China relations are very positive, this does not necessarily mean the United States is losing influence in Southeast Asia, or that ASEAN members are "bandwagoning" with China--in fact, they are hedging by keeping America engaged and facilitating a continued U.S. military presence. While ASEAN-China relations are relatively benign today, in the future several sources of potential friction could create problems in Sino-U.S. relations: these are Taiwan, Burma, and the South China Sea dispute. This monograph examines each of these scenarios in turn.