DHS's public awareness campaign for reporting suspicious activity, often referenced in BSIS terrorism-awareness modules, is:

Explanation

'If You See Something, Say Something' is the registered DHS campaign emphasizing that observation of behavior (not appearance, race, ethnicity, or religion) is what matters, and that the public — including security officers — are critical reporting partners. The campaign directs reports to local law enforcement or 911 for emergencies, the FBI for federal jurisdiction (especially terrorism), and tip lines such as 1-855-TELL-FBI. Officers are trained to report observable behavior, not based on identity characteristics — which would violate civil-rights protections (28 CFR Part 23, federal civil-rights statutes).