This article introduces an evolutionary framework for the de-escalation of protracted conflicts. Key variables are political shocks, expectancy revision, policy entrepreneurship, third-party pressure, and reciprocity. The model is tested in the context of the Israeli-Palestinian case, 1979-98. A quantitative assessment is made with the use of Middle East KEDS data as well as a qualitative assessment of the intervening impact of shocks on the expectations and strategies of key decisionmakers. The results show that while shocks by themselves did not always change the expectations and strategies of the Palestinian and Israeli leaderships, their combined influence with entrepreneurship, third-party pressure, and reciprocity did indeed improve the frequency of Israeli and Palestinian agreements in the long term. In fact, the joint effect of shocks and entrepreneurship appears to play a crucial first step in the overall de-escalation process. In addition, shocks had important intervening effects for both sides by reducing major institutional constraints that paved the way for an initial political settlement reached in the 1993 Oslo Accords. Finally, the results suggest that without political shocks, inertia overrides the inclination of decisionmakers to pursue new, risky policies that could undermine their political positions.