The Worldwide Incidents Tracking System is the National Counterterrorism Center's database of terrorist incidents.

According to NCTC definition, terrorism occurs when groups or individuals acting on political motivation deliberately or recklessly attack civilians/non-combatants or their property and the attack does not fall into another special category of political violence, such as crime, rioting, or tribal violence. For further guidance on criteria, please see the Methodology page.

The WITS database includes data from 1/1/2004 to 9/30/2009.