Theories of change explain how conflicts are prevented, mitigated, managed, resolved or transformed.
Theories of change have two parts. First is a theory about what factors are driving or mitigating conflict. Second is a theory about what can be done about conflict. A theory of change is about how some driving or mitigating factor of the context (factor) can be changed with some peacebuilding action (action) to achieve an impact that prevents violence or builds peace.

Theory of Change Formula – (fill in the blanks)
If these factors are driving or mitigating violence, then these actions will achieve these impacts to reduce violence, foster perceptions of justice, or strengthen peaceful relations between groups.

A theory of change contains each of these three components: factors, actions, and impacts. The following case study provides an example.

Factors (conflict assessment). An NGO assessed the local context and found the lack of representative local decision-making bodies, interethnic tensions, and economic deprivation were all important factors driving communities toward violence.

Actions (type of peacebuilding effort). To address these three interrelated drivers of conflict, the NGO created an integrated program to set up local community development councils made up of male and female representatives from different ethnic groups to foster local governance, and also incentivized interethnic cooperation through offering microcredit loans to multiethnic business proposals intended to foster economic development.

Impacts (peacebuilding effects). The NGO found that the communities where they worked were less susceptible to insurgent recruitment, experienced less violence, and developed sustainable programs that fostered viable economic systems.

The book Conflict Assessment and Peacebuilding Planning also includes:

A list of the most widely referenced theories of change in the field of peacebuilding
A discussion of “results chains” that link micro and macro theories of change
A guide to how to develop and collect theories of change to improve peacebuilding practice