How did China and Viet Nam each react to the crisis in their relations between 1975 and 1979? Why did the Chinese ultimately wage war against the Vietnamese? This work is an historical case study that addresses these central questions. International crisis management case studies done by Allen Whiting, Ole Holsti, Alexander George, and Richard Smoke form a base for developing the analysis. Journalistic reports and government documents constitute the majority of the primary source materials used. Both Hanoi and Beijing felt the other posed a serious threat to its national security. Each side sought to communicate its concern to the other through a series of signals. This study focuses mainly on the pattern of Chinese signals, as Beijing responded to what is considered increasingly unacceptable behavior by Hanoi. The means of delivery, the rhetorical intensity the level of issuing authority, and the relative timing of the signals all showed indications of escalating as the crisis became more severe. The paper proposes an index of indicators by which to judge the progress of crisis control. One of the chief difficulties in the Sino-Vietnamese dispute was a conflict of perceptions. Each side was using a different perspective in viewing its own and the other side's position. By using indicators to understand crisis development more fully, decision-makers may be able to exercise crisis management more effectively.