Is peace more likely to prevail when the peace accord includes civil society actors such as religious groups, women's organizations, and human rights groups? This is the first statistical study that explores this issue. The article develops key claims in previous research regarding the role of civil society actors and durable peace, and proposes a set of hypotheses that focus on legitimacy in this process. The hypotheses are examined by employing unique data on the inclusion of civil society actors in all peace agreements in the post–Cold War period. The statistical analysis shows that inclusion of civil society actors in the peace settlement increases the durability of peace. The results further demonstrate that peace accords with involvement from civil society actors and political parties in combination are more likely to see peace prevail. The findings also suggest that inclusion of civil society has a particularly profound effect on the prospects for overall peace in nondemocratic societies.