What are the major international threats to the tenure of authoritarian rulers? What factors make authoritarian rulers more or less vulnerable to these external challenges? In this paper, we focus on two such threats – international democracy promotion and the diffusion of political change – and draw the following conclusions. One is that authoritarian leaders view both threats as significant because they have the potential to amplify domestic vulnerabilities and remove authoritarian rulers from power. Another is that cross-national waves of political change appear to be far more menacing developments than international democracy promotion. A third is that variation in how authoritarian rulers read the gravity of these threats depends upon four factors: the openness of the regime; the vigilance of its rulers as a result of pathways to power and their tenure in office; the type of political system; and the relationship of the regime to the West.