University of Notre Dame
Kroc Institutde for International Peace Studies

Kristen Wall and David Cortright 

Conflict data sets enable peace scholars to identify key practices that make a difference in peacebuilding.

Take, for example, the practice of peacekeeping. One of the strongest findings to emerge from empirical research is that impartial peacekeeping forces make a significant difference for sustaining peace in post-conflict societies. A peace settlement alone does not guarantee an end to armed conflict in societies that are still highly armed and fractured. Fighting often resumes unless a third party steps in to verify or enforce a ceasefire and post-conflict agreement.

The importance of third-party peacekeeping is reflected in the prevalence of such provisions in comprehensive peace agreements. More than one third (11 out of 29) of the peace settlements profiled in the Peace Accords Matrix have provisions for United Nations peacekeeping missions. More than two thirds (22 out of 29) include provisions for international/internal verification of the terms of peace agreements. One fifth (6 out of 29) have provisions for regional peacekeeping.

WHAT THE STUDIES SHOW

Several major studies confirm the importance of peacekeeping missions for preventing renewed hostilities.

Virginia Page Fortna examined dozens of armed conflicts that ended with ceasefires and negotiated peace agreements, using a database that covers 94 cases of ceasefires in 60 civil wars from 1989 to 1999. She compares cases where third-party peacekeepers were deployed with those where belligerents were left to their own devices. The presence of third-party peacekeepers reduced the risk of renewed war by between 55 and 85 percent.1 Multi-dimensional peacekeeping missions that incorporate civilian peacebuilding activities have “the largest substantial effects” on preserving peace in the aftermath of civil conflict, she writes. More limited UN peacekeeping missions also have “a clear stabilizing effect.”2 Both forms of peacekeeping have positive impacts. Her conclusion: “The statistical evidence is overwhelming … peacekeeping works.”3

In a study of 60 civil wars, the presence of third-party peacekeepers reduced the risk of renewed war between 55 and 85 percent.

Michael Doyle and Nicholas Sambanis compiled a database of 121 UN peace operations after civil conflicts from 1945 through the end of 1999.4 They “find very strong support in the data” for the hypothesis that UN operations have “a positive and significant effect” on peacebuilding.

They test for probabilities of success in a hypothetical model where there is a negotiated accord and broad UN mission, versus one with no treaty or UN mission. In cases without a UN mission, the likelihood of success drops from an initial value of about 80 percent to less than 5 percent.5 Their study finds that the negotiation of a peace agreement and the presence of UN peacekeepers are key factors in achieving a successful end to armed conflict.

INCENTIVES FOR PEACE AND WAR

A peacekeeping presence changes incentives for peace and war. It reduces uncertainty about each side’s intentions and prevents and controls accidental outbreaks of violence that could escalate into renewed war. Without third-party security guarantees, settlement implementation can fail because combatant parties cannot make a credible commitment to abide by negotiated terms. Negotiations that succeed in naming a trusted third party to enforce and verify demobilization overcome this barrier.

Peacekeeping reduces uncertainty about each side’s intentions and helps prevent and control accidental outbreaks of violence.

The more credible a third-party force appears to be during negotiations, the more likely combatants are to sign and implement peace accords. The benefits of third-party intervention are strongest when warring parties freely enter into negotiations, as opposed to being forced to bargain.

It is vital that third-party intervention forces are available to deploy promptly when an agreement is signed; otherwise hostilities can resume and more vulnerable parties will be at risk. Likewise, it is essential that third parties stay for the duration of the transition period from militarized hostilities to institutionalized power sharing to prevent the resumption of hostilities.6

These and other lessons drawn from conflict research and databases can help peacebuilders improve the prospects for the successful implementation of peace accords.

Kristen Wall is research associate in policy studies at the Kroc Institute for International Peace Studies.

David Cortright is director of policy studies at the Kroc Institute. 

1 Virginia Page Fortna, Does Peacekeeping Work? Shaping Belligerents’ Choices after Civil War (Princeton, NJ: Princeton University Press, 2008), 125; Virginia Page Fortna and Lise Morjé Howard, “Pitfalls and Prospects in the Peacekeeping Literature,” Annual Review of Political Science 11, 2008: 289.
2 Virginia Page Fortna, Does Peacekeeping Work? Shaping Belligerents’ Choices after Civil War (Princeton, NJ: Princeton University Press, 2008), 109, 111.
3 Virginia Page Fortna, Does Peacekeeping Work? Shaping Belligerents’ Choices after Civil War (Princeton, NJ: Princeton University Press, 2008), 6, 9-10, 106, 116.
4 Michael Doyle and Nicholas Sambanis, Making War and Building Peace: United Nations Peace Operations (Princeton, NJ: Princeton University Press, 2006), 72.
5 Michael Doyle and Nicholas Sambanis, Making War and Building Peace: United Nations Peace Operations (Princeton, NJ: Princeton University Press, 2006), 128.
6 Barbara Walter. Committing to Peace: The Successful Settlement of Civil Wars. (Princeton: Princeton University Press, 2002).