Jaremey McMullin is exploring youth peacebuilding processes through a multi-year project, 'Motorcycling as Peacebuilding in Liberia', that analyses the peacebuilding impacts and challenges of the commercial motorcycling sector in Liberia. His other primary research interest areas are the disarmament, demobilisation, and reintegration (DDR) of ex-combatants and the politics of veterans' return from war. This research interprets the impacts of reintegration and veterans' assistance programmes on post-conflict identities, conflict resolution, and security, and identifies the consequences of incomplete reintegration. A related project considers veteran-led modalities of assistance and veteran-to-veteran peer support in the United States. His 2013 monograph, Ex-Combatants and the Post-Conflict State: Challenges of Reintegration, was published in the Rethinking Political Violence series by Palgrave Macmillan. He has published articles and book chapters on the narration of youth peacebuilding identity and reintegration strategies (Review of International Studies), and on ex-combatant reintegration in Namibia, Mozambique, Sierra Leone, Liberia, and the United States (Review of International Studies, International Peacekeeping, International Feminist Journal of Politics, and Conflict, Security & Development). He has also published articles on child soldiering (Third World Quarterly) and the role of non-state criminal groups during conflict (Civil Wars).

He directed and produced a documentary short film series on everyday peace, Liberia: Legacies of Peace (2019) and another documentary short, Silkies (2020), on prevention of veteran suicide. He has written several reports and evaluations for the Disarmament, Demobilization and Reintegration Section at the United Nations Department of Peace Operations, including a 2020 report, 'The Legacy of DDR in Liberia', and he serves on the Research Working Group of the Integrated DDR Training Group.

- Ex-combatant disarmament, demobilisation and reintegration (DDR)

- Veterans’ politics and post-war welfare policy

- Youth livelihood, peacebuilding, social movements, and political participation

- Cross-border youth dialogue and community-based mediation for conflict-affected groups

- Peacekeeping and peacebuilding

- Resistance and protest movements after war

- Documentary filmmaking and peace research

- Qualitative research methods, field research, and research ethics

- The United Nations