Contact UsWe welcome questions and feedback from users. For the quickest answers, please consult the FAQs below to see if your question has already been addressed before submitting it using the form below.
Why has the licence for using GTD changed?
What should I do if I’m unsure whether I meet the individual use definition?
If you’re unsure if you or the organization you represent meet the definition for individual use, please complete the contact form for organizational use and explain your situation in the comments box. We will be in touch to discuss your question.
Can I use the GTD for my research/analysis/project?
Yes, we encourage researchers, analysts, and scholars to use the GTD in their work. Users can download the dataset by following the links on the “Access the GTD” pages for “Individual Use”. You will be required to accept the End User Agreement. It is vital that you cite the GTD appropriately, acknowledge any changes you make to the GTD in your analysis, and carefully read the End User Agreement as there are important restrictions to ensure that the data are only used for the purpose of better understanding, or defeating terrorism.
Our recommended citation for the database is:
National Consortium for the Study of Terrorism and Responses to Terrorism (START), University of Maryland. (2019). The Global Terrorism Database (GTD) [Data file]. Retrieved from https://www.start.umd.edu/gtd
How can US Government employees and contractors download the GTD?
United States Government (USG) users have "Government Purpose" rights in the portions of the data funded by the USG. To access the GTD, USG users can select "Organizational Use" and fill out the brief form to request access. Our distribution partner, CHC Global will confirm access within two business days. Non-government organizations interested in using the GTD for USG purposes should request access through their USG client. Non-government organizations interested in using the GTD for non-USG purposes should select "Organizational Use," and fill out the brief form to request access. CHC Global will respond with additional information about licensing within two business days.
Can I still search and browse the data without downloading the file?
Why is there a delay in releasing the data?
When fully funded, GTD source document collection occurs daily; however, systematic curation of structured data requires considerable time and effort on the part of the research team. The database is typically updated annually for non-commercial users. Commercial users may have access to preliminary data updates on a more frequent basis. The GTD is produced with the intent of providing a long term view of terrorism and as such, we prioritize accuracy and completeness.
Why are the data for 1993 missing?
The original PGIS data, upon which the 1970-1997 GTD data are based, consisted of hard-copy index cards, which were subsequently coded electronically by START researchers. Unfortunately, the set of cards for 1993 was lost prior to PGIS handing the data over to START. Country-level statistics for 1993, including number of incidents, number of fatalities, number injured, number of U.S. fatalities, and number of U.S. injured were recovered from a PGIS Risk Assessment Report for 1993. These figures are available in the appendix of the GTD Codebook.
Why doesn't GTD have a single definition of terrorism?
In the absence of a universally accepted definition of terrorism, the GTD uses several coded criteria to cover key characteristics of terrorism through a combination of inclusiveness and filtering. The goal is to have a dataset that is useful to as many interested users as possible.
Please see our GTD Codebook for more details.
I came across an incident in the database that I do not believe is terrorism. Why was it included?
While the GTD inclusion criteria offer a comprehensive definition of terrorism, we encourage users to take advantage of the GTD's flexibility to restrict the data according to their definitional preferences. This includes filtering search results based on whether the coder noted some uncertainty whether an incident meets the criteria for inclusion ("Doubt Terrorism Proper," systematically available for post-1997 cases only). Also, users can filter search results based on which of the following three criteria are met (available for all cases):
Criterion 1: The act must be aimed at attaining a political, economic, religious, or social goal.
Criterion 2: There must be evidence of an intention to coerce, intimidate, or convey some other message to a larger audience (or audiences) than the immediate victims.
Criterion 3: The action must be outside the context of legitimate warfare activities, insofar as it targets non-combatants.
Please see our GTD Codebook for more details.
I found a factual error or a case missing from the database. How did this happen?
While every effort is made for each incident to corroborate facts from multiple independent sources and to eliminate errors through a systematic review process, the magnitude of the database (more than 200,000 discrete incidents) means that occasionally an error will evade detection and appear in the database or a valid incident will not be recorded. In these cases, we rely on users who become aware of such an error to contact us and let us know so we can review the case and make any appropriate corrections.
Does the GTD include foiled and failed plots or threats to attack?
Although the GTD does include failed attacks, it does not include foiled or failed plots, the distinction being that the attack must actually be attempted to qualify for inclusion in the database. Likewise, the GTD does include attacks in which violence is threatened as a means of coercion, but does not include threats to attack where no action is taken.
Does the GTD include insurgency?
To some degree, the GTD does include acts that occur either during a specific insurgency or that closely resemble an insurgent attack against a military target. Without clear definitions of terrorism and insurgency in the literature these types of actions can overlap, with insurgent organizations using violence against non-combatants alongside attacks directed at combatants. While terrorism as a tactic has been used within a number of insurgent campaigns, the GTD should not be viewed as a comprehensive collection of insurgent attacks.
Does the GTD include incidents of state terrorism?
No, the GTD is limited to acts of non-state terrorism. One of the three necessary criteria for inclusion is that there must be sub-national perpetrators. The database does not exclude cases in which states sponsor attacks by non-state actors that otherwise meet the inclusion criteria. If it is unclear if an attack was carried out by state actors, the event may be included in the database and marked as “Doubt Terrorism Proper: State Actor.”
Please see our GTD Codebook for more details.
Does the GTD include the RAND database and/or the WITS database?
The RAND Database of Worldwide Terrorism Incidents (RDWTI) and the Worldwide Incident Tracking System (WITS) compiled by the National Counterterrorism Center (NCTC) are two important data collection efforts that coincided with the collection of the GTD for several years. These data collection efforts were conducted by RAND and NCTC independently of START’s GTD collection effort, with their own definitions, inclusion practices, and source requirements. The GTD does not systematically include records from either RDWTI or WITS. On a very limited basis, the GTD may reference other databases or chronologies among the sources of information for individual cases. The RDWTI and the WITS databases were never used as the only sources for an event’s inclusion in the GTD and neither of these databases were comprehensively incorporated into the GTD. All primary and supplemental data collection efforts that comprise the GTD are listed in the GTD Codebook. Supplemental data collection efforts are subject to the same GTD definitional criteria and inclusion practices as the primary data collection process.
Who makes the decisions about what to include as an incident?
The basic criteria were formulated by the GTD Advisory Board, and are documented in the GTD Codebook. In practice, trained researchers decide whether a case they are working on fulfills these criteria, and this decision is reviewed by GTD supervisory staff. In cases where determination is difficult, the case is raised for review and deliberation among the full data collection team.
Is there a methodological reason for the decline in the data between 1997 and 1998, and the increases since 2008 and 2012?
While efforts have been made to assure the continuity of the data from 1970 to the present, users should keep in mind that the data collection was done as events occurred up to 1997, retrospectively between 1998 and 2007, and again concurrently with the events after 2008. This distinction is important because some media sources have since become unavailable, hampering efforts to collect a complete census of terrorist attacks between 1998 and 2007. Moreover, since moving the ongoing collection of the GTD to the University of Maryland in the Spring of 2012, START staff have made significant improvements to the methodology that is used to compile the database. These changes, which are described both in the GTD Codebook and in this START Discussion Point on The Benefits and Drawbacks of Methodological Advancements in Data Collection and Coding: Insights from the Global Terrorism Database (GTD), have improved the comprehensiveness of the database. Thus, users should note that differences in levels of attacks before and after January 1, 1998, before and after April 1, 2008, and before and after January 1, 2012 may be at least partially explained by differences in data collection; and researchers should adjust for these differences when modeling the data.
In general, trends over time should be interpreted with caution due to the possible effects of changing availability of reliable source materials. Likewise, the GTD is not directly comparable to other sources of data on terrorism, as differences in definitions, sources, and workflows will produce misleading inferences.
I need to provide raw GTD data for an academic journal replication archive. Do I need permission?
Can the GTD be used as a source of information on legal dispositions of criminal charges?
No. Statistical information contained in the Global Terrorism Database is based on reports from a variety of open media sources. Information is not added to the GTD unless and until we have determined the sources are credible. Users should not infer any additional actions or results beyond what is presented in a GTD entry and specifically, users should not infer an individual associated with a particular incident was tried and convicted of terrorism or any other criminal offense. If new documentation about an event becomes available, an entry may be modified, as necessary and appropriate.
Who funds the database?
The collection of the GTD is currently funded by the German Federal Foreign Office (FFO) and the United Kingdom Foreign, Commonwealth, and Development Office (FCDO).
START is actively considering funding solutions to continue to maintain and improve the GTD.
In the past, GTD collection, maintenance, and improvements have been supported by:
- United States National Institute of Justice
- United States Department of Homeland Security, Science and Technology Directorate
- United States Department of State, Bureau of Counterterrorism and Countering Violent Extremism
- United States Department of Defense, Combating Terrorism Technical Support Office
- German Federal Foreign Office
All decisions about GTD data collection are made independently by the research team. The GTD does not represent the official position of any funding agency.
Get in Touch
Please select the team you would like to get in touch with from the list below:
GTD Media Enquiries
For general media inquiries or insight from START researchers, contact START’s Communications Director here.
GTD Analyst Team
For questions or feedback about the GTD, the data collection process, and analysis contact the GTD team at START here.
For questions about licensing the GTD for personal or organizational use, or consultation with GTD researchers, contact CHC Global here.