Violent conflict is arguably the single most avoidable cause of human suffering in the world. Not only does violent conflict cause death and suffering directly, it also has severe negative impact on other cause areas. When violent conflict is reduced, Malaria cases decline. When violent conflict ends, gender-based violence declines. When there is no violence, fewer people starve. Reducing violent conflict has a manifold effect on reducing suffering in the world.
States and other actors try a variety of interventions to reduce violence. Disarmament, armament, peacekeeping, development aid, international institutions, education–the variety of possible interventions is dramatic. Many of these, such as disarmament, armament and aid, have received a significant amount of attention and financial support from governments and international organizations. However, I would argue that there is another intervention that is not just very effective, but is quite neglected and has significant tractability.
In order to reduce violent conflict, I propose that Open Philanthropy adopts peacebuilding as a cause area. In my opinion peacebuilding is an incredibly important, neglected, and very effective way to address violent conflict in the world.
I will first explain why peacebuilding is so important and relevant to solving violent conflict. From there I will then discuss peacekeeping’s importance, negelectedness and tractability.
Peacebuilding is the practice of preventing conflict before it arises or returns. It is an effort to use politics, social development, dialogue and any and all tools to create communities that feel safer and more just. The theory of change here is that insecurity and injustice are two of the primary causes of violent conflict. In order to reduce violent conflict, then, we need to reduce insecurity and injustice in societies where they are especially prevalent.
To paraphrase a professional in peacebuilding, peacebuilding is the intersection of foreign policy and development. It is a patient and persistent view on how to make communities better while also understanding power and politics, and how to work with these dynamics to make communities safer and more just. Peacebuilding tries to identify the 'core' of a conflict, the the source of its malignancy, in order to root out the true issue and not just the cruel ways in which it is manifested. Peacebuilding addresses the disease rather than the symptoms.
The term peacebuilding is ambiguous, and many would include disarmament and any of the other interventions mentioned in the introduction as peacebuilding. For this cause area I argue that peacebuilding that address social and political issues in societies that might devolve into violent conflict.
These interventions could include civic engagement with politicians, religious, and social leaders; initiatives to empower youth and children within a community; working with media to create journalistic freedom and to avoid using mass media for violent purposes; and other ‘difficult to quantify’ efforts that are meant to strengthen a society and to create pluralistic and possibly democratic societies.
While violent conflict today is mostly limited to conventional warfare methods, it could include on its worst days nuclear, biological and chemical weapons. Violent conflict can represent both existential and catastrophic risks for humanity. Even if peacebuilding today does not work with conflicts that could have clear global consequences, conflict can be unpredictable. Developing the field of peacebuilding today could have immeasurably positive consequences for tomorrow by reducing the risk for globally catastrophic warfare.
Below are arguments for the effectiveness, neglectedness, and tractability of peacebuilding.
Peacebuilding prevents violent conflict. While reducing the number of people killed and injured directly in conflict has intrinsic values, it is very relevant to also understand the manifold effects of preventing conflict. For example, peacebuilding can protect the economies of countries vulnerable to conflict. According to the Institute for Economics and Peace (IEP), the global economic impact of violence was $14.4 trillion PPP in 2019, which was equivalent to 10.5 percent of global GDP. A reduction of 2% of violent conflict could be worth all of the official development aid distributed by all governments in a single year. Noting that violent conflict today regularly happens in some of the least developed world, any improvement in GDP could have a much larger relative impact than the absolute number might suggest.
In addition, preventing a conflict can have a significant counterfactual benefit. Again according to the IEP, preventing conflict in Rwanda could have an ROI of 16X. For every US dollar spent on peacebuilding before the 1994 conflict in Rwanda could have saved 16 US dollars over the past two decades.
However, counterfactuals do not actually demonstrate successful peacebuilding measures. This is part of the weakness of an intervention that is meant to prevent conflict–it is difficult to measure something that does not happen. This is discussed further in the neglectedness section. However, it is worth noting that there are examples of where peacebuilding has been especially effective, namely Northern Ireland from the 1990s onwards and the success of peace and reconciliation efforts during and after the fall of Apartheid from 1990 onwards.
There is clear anecdotal evidence for the importance of peacebuilding, though. In 2020 there was an open debate in the UN Security Council that clearly vouched for the importance of peacebuilding and that there was room for developing better tools for the sector. 
In addition, there is also the issue of measuring the efforts of peacebuilding. Even if we cannot be certain of what conflicts peacebuilding has or has not prevented, we should be able to measure the impact of peacebuilding in the communities in which they operate. This is easier said than done, of course, and is actually a very exciting opportunity for improvement within the cause area. There are efforts underway to develop robust measurement methods, and they need help. Such methods that combine both qualitative and quantitative methods can also work as frameworks for other cause areas that are currently difficult to measure using quantitative methods.
Preventing violent conflict and creating safer and more just communities can have an extremely positive impact.
Peacebuilding is neglected and is regularly under-prioritized. According to the UN Peacebuilding Commission, the proportion of Official Direct Aid given out by governments for peacebuilding has declined from 18.4% in 2011 to 13.5% in 2019.
Why peacebuilding is being deprioritized is uncertain. The World Bank argues that peacebuilding is neglected because it is difficult to promote in public relations and lacks counterfactuals. ‘Prevention lacks positive publicity, as the existence of a direct link between specific policy actions and the resulting absence of violence is often hard to prove.’  Despite the utility of prevention, it is difficult to sell prevention compared to investing in other forms of development aid that can create objects such as dams or clear outcomes like elections.
Not only is funding for all peacebuilding decreasing, it seems that the funding for the type of peacebuilding that we are discussing here is even more precarious. This is because much of the peacebuilding work relevant to this discussion is not done by states or their development agencies. Typically this work is done by smaller organizations and some international organizations such as the UN. This means that much of the work is project-based and without clear funding avenues.
Speaking with Search for Common Ground, an active independent organization in peacebuilding, most of their funding is project-based with an average length of 21 months. This does not allow them to really invest in an institution separate from specific projects and to develop an institution that creates a larger impact through working on projects and ideas that might not fit the granting interests of larger organizations that can shape the field.
As we begin to consider tractability, you will see that Open Philanthropy might be in a unique position to support the development of an influential, well established and well researched field.
There are clear opportunities to help peacebuilding reduce violent conflict.
Violent conflict can be reduced. In the period from 1990 to 2019, the number of absolute deaths from conflict globally has decreased by 46%, despite the global population increasing.  It is possible for violent conflict to be prevented. However, the number of conflicts, depending on how you measure it, has gone up in the last few years.  While the number of people dying in conflicts has reduced, there is still a lot of room for preventing conflicts in the first place. The fewer the conflicts, the fewer economic, social and political disturbances. The less risk for major conflicts that can cause major fatalities and destruction.
There are concrete ways in which a funder other than the UN or a government can support peacebuilding. Not only is the funding not currently there for these efforts, but there is also a low likelihood that any support would be fungible–official aid givers do not think in the same manner that private donors, especially Open Philanthropy, might think, and seem less likely to support interventions that are either not run by a state agency or specifically part of a state's foreign policy. As in other policy areas, we know that states do not choose their interventions entirely based on effectiveness.
The Stockholm International Peace Research Institute identifies three main areas where funding can directly help peacebuilding:
- Coherence, or cooperation and common forms of measurement and oversight;
- Resilience to keep a plurality of different organizations open and working in an area that can be quickly dominated by large actors;
- Sustainability to support research into methods of transferring peacebuilding responsibility to local governments and other social actors. 
I believe that Open Philanthropy is especially suited to supporting peacebuilding in funding coherence and resilience efforts. I suggest resilience because Open Philanthropy is interested in hits-based funding and is always interested in a diversity of approaches. I also suggest coherence because this work has an especially interesting opportunity to work on the challenge of measuring impact in social issues. For example, The Search For Common Ground organization is attempting to create a method of measuring impact in peacebuilding called The Global Impact Framework. They are trying to create a method that is both quantitative and qualitative using expert defined measurements, perceived outcomes by those in the conflict area, and measuring outcomes over time.  What is especially interesting is that even with the qualitative nature of working with social issues, the framework is not dependent on location or context. It should be able to be used in a variety of circumstances and have data that should be able to be comparable to other peacebuilding efforts.
What is particularly exciting about this is that these measurement methods can arguably be applied to measure other social interventions, which would be an exciting opportunity to help measure the impact of efforts to improve the world that do not have such clear methods of measure as health or economic interventions. If peacebuilding is able to define a method for measuring the impact of social and political efforts like peacebuilding, it will have a significant effect on effectiveness-oriented donors' abilities to measure unusual and more socially oriented projects than it is able to currently.
Of course, peacebuilding is not a perfect cause area. First, it is unclear what the actual impact multiplier is. This is partly because the effects of peacebuilding are diffuse and multi-layered, but also because it is a varied and poorly defined cause area. What do we count as peacebuilding? To what degree can we count better medical interventions in a former war zone as the success of peacebuilding? As discussed above, there is not a good method for measuring this, and there very well might never be a perfect method either. However, I believe that there can be satisfactory methods, and funding further peacebuilding work could give the field an opportunity to discover the most effective interventions.
There is also a question of if international aid is in fact good for its recipients. Is international aid inherently a colonial or imperialist effort of western states to make other countries ‘better’ and developed, especially when these same western states were responsible for both World Wars?
We also need to address the counterfactual of counterfactuals. How do we know that Syria would not be better without international support? How do we know any other country that has improved over time with international aid would not have recovered in its own fashion if left to its own devices? It is difficult to argue for international investment in peacebuilding if the alternative, local efforts are never given a chance themselves.
There is also a chance that the interventions focused on here are not the best peacebuilding efforts. It is possible disarmament is more effective than improving societies, or that a strong military is the best deterrent to large-scale conflict. Again, this is a hard counterfactual to discuss since there is not much data available on other efforts than those that militaries attempt to do, but it is possible that peacebuilding is not the most effective. I would argue, however, that this argument does not diminish peacebuilding’s neglectedness or tractability.
All of these criticisms should be further investigated. There are also surely other valid criticisms of this cause area that I have missed here, and any omissions are entirely my own and not a reflection on the seriousness of other criticisms.
I do think that reducing violent conflict is a very worthy and useful cause and that investing in peacebuilding is could have an exceptional return over time. Reducing violent conflict improves the lives of the most vulnerable people in the world by keeping them safe and allowing economic development, medical intervention and peace to create better communities and more comfortable lives. Not only are the immediate effects obvious, but there is the significant opportunity to reduce the chance of catastrophic war in the future if we can discover the best ways to prevent conflict today.
Peacebuilding that focuses on political and social interventions is a promising intervention to reduce violent conflict that is clearly important, neglected compared to other efforts to prevent conflict, and has clear ways in which funding can be put to very good use.
Peacebuilding deserves our attention and support.