DCAF - /ˈdiˌkæf/; Geneva Centre for Security Sector Governance (French: Centre pour la gouvernance du secteur de la sécurité, Genève, German: Das Genfer Zentrum für die Gouvernanz des Sicherheitssektors) is an intergovernmental foundation-based think tank[1] that provides research and project support to states and international actors in improving security sector governance and reform (SSG and SSR).

DCAF was established in 2000 as the 'Geneva Centre for the Democratic Control of Armed Forces' in the Canton of Geneva by the Swiss government and as of 2023 employs around 220 staff in 16 offices.

The Centre's founding mandate was to assist security institutions to reform themselves in ways that would help stabilize the fragile peace following the 1990s Balkans conflicts and during the democratic transitions of Central and Eastern Europe.

[1] Likewise, an external evaluation published in 2014 assessed that DCAF "has an excellent reputation as an organization with solid expertise".

[2] As of 2023 it comprises 54 states and the Canton of Geneva as well as four governments and two international organizations that hold observer status.