Summary

Uncertainty is pervasive in international politics. This uncertainty can have many sources. Each source has different origins and implications for the likelihood of conflict. Existing theories focus on three sources: (1) uncertainty due to asymmetric information about adversary traits that affect war payoffs, (2) uncertainty about adversary intentions, and (3) fundamental uncertainty about conflict-relevant processes. Scholarship details the implications of each type of uncertainty for war and peace as well as the prospects for reducing the uncertainty. While theoretical work is quite rich, empirical studies generally lag behind due to measurement challenges and difficulties in specifying clear, testable implications. Nonetheless, using novel proxies for different forms of uncertainty has generated notable progress.