Under what conditions do states die? Survival is often assumed to be the primary goal of states. Yet international relations scholars have not previously examined the rate or the causes of state death in a systematic way. I argue that buffer states - states caught between two rivals - are particularly vulnerable to being coerced out of existence. Each rival is afraid that its opponent will conquer the buffer that lies between them, gaining strength and strategic advantage. The rivals' inability to credibly commit to preserving the buffer state's sovereignty means that buffer states are extremely vulnerable to conquest. Using event history analysis, I test this argument while controlling for traditional realist variables such as power and alliances, as well as for changes in the post-World War II era. The analysis generates three major findings: buffer states are significantly more likely to die than are nonbuffer states; violent state death (conquest and occupation) virtually ceases after 1945; and the relationship between power and state survival is tenuous.