This SWAC/OECD study maps the evolution of violence across North and West Africa, with a particular focus on Mali, Lake Chad and Libya. In the regions experiencing the highest levels of political insecurity, it identifies whether and how conflicts tend to cluster or spread, potentially across national borders. The work is based on a new spatial indicator of political violence designed to assess the long-term evolution of conflicts and provide policy options. It uses granular data to assess the intensity and geographical distribution of violence in the region since 1997. It finds that the last five years in North and West Africa have been the most violent, with more than 60 000 people killed between January 2015 and the end of 2019. More than 40% of violent events and fatalities occur within 100-km of a land border, and 10% of deaths from political violence occur less than 10-km from a border. The report calls upon the region’s states and the international community to promote regional initiatives to restore state legitimacy, increase investment in border regions and better protect civilians.