Peacekeeping by the United Nations is a role of the UN's Department of Peace Operations as an "instrument developed by the organization as a way to help countries torn by conflict to create the conditions for lasting peace". It is distinguished from peacebuilding, peacemaking, and peace enforcement although the United Nations does acknowledge that all activities are "mutually reinforcing" and that overlap between them is frequent in practice.

The Department of Peace Operations (DPO) is a department of the United Nations charged with the planning, preparation, management and direction of UN peacekeeping operations. Previously known as the Department of Peacekeeping Operations (DPKO), it was created in March 1992, as part of a restructuring of the UN's peace and security apparatus. The DPO retains the core functions and responsibilities of its predecessor, with a greater emphasis on cohesion, integrating different resources and knowledge, and promoting human rights.