# Cybersecurity and Infrastructure Security Agency **Domain:** Cybersecurity / Critical Infrastructure / United States Government **Doc Type:** Agency Node **Maturity:** Canonical ## Definition The **Cybersecurity and Infrastructure Security Agency**, or **CISA**, is the operational cybersecurity and critical-infrastructure security agency of the U.S. Department of Homeland Security. ## Journal Context CISA's December 2024 [[wiki/Mobile Communications Best Practice Guidance|Mobile Communications Best Practice Guidance]] addressed senior government and political figures and other [[wiki/Highly Targeted Individuals|highly targeted individuals]] following compromises affecting U.S. telecommunications infrastructure. ## Sources / Provenance - [CISA — official site](https://www.cisa.gov/) - [[journal/2026-08-21 - Cyber Terrorism Is Terrorism|Cyber Terrorism Is Terrorism]] ## See Also [[wiki/Cybersecurity|Cybersecurity]], [[wiki/Incident Response|Incident Response]], [[wiki/National Security|National Security]]