This project aims to improve understanding of, and responses to, the phenomenon of lone actors through analysis of comprehensive data on cases from across Europe.

This article provides an in‐depth assessment of lone actor terrorists’ attack planning and preparation.

The term “Lone Actor” has been applied to a variety of violent individuals who are thought to act out of ideological motivations using terrorist tactics.

The research group on terrorism and political violence studies the phenomena of terrorism-related and other politically motivated violence.

This research note argues that the “lone wolf” typology should be fundamentally reconsidered.

Research goal: To support the design of technologies (counter-measures and communication measures) for the prevention, interdiction and mitigation of lone actor extremist events (LOEEs), which are hard to anticipate, yet can be highly damaging to local and national communities and therefore must be…

Recently, Europe was again shaken by some attacks. This ‘Elementair Deeltje’ places terrorism in a historical perspective and gives an up-to-date overview of this form of political violence.

Jelle van Buuren bespreekt de link tussen radicalisering en psychiatrische problematiek.

During the 1980s and early 2000s, authors like Alex Schmid and Andrew Silke demonstrated the paucity of first-hand insights being used to study terrorism and the consequences this had for the reliability of the findings beings presented. But to what extent have these issues endured?

On 20-21 June, the Society for Terrorism Research (STR) held its annual conference in Oslo. The Center for Research on Extremism (C-REX) of the University of Oslo led by Professor dr. Tore Bjørgo hosted one of the main academic conferences in the field of terrorism studies. The central theme was the…

It is in the interest of all democracies for young people to learn the value of free debate, even on sensitive and potentially divisive issues like terrorism, argue Thorbjørn Jagland (secretary general of the Council of Europe), Sayeeda Warsi (UK parliamentarian), and Francesco Ragazzi (Institute of…

In the track Governance of radicalism, extremism and terrorism you will be familiarised with the academic debate regarding these contested concepts.

As terrorism scholars, we are intrigued by those who engage in violence. We study their motivations, tactics, ideology, organisational structures, and pathways to (de-)mobilisation, hoping to better understand terrorism and how we can counter it. Far less attention is paid to what happens after an attack…

Terrorism only poses a small risk to people but tends to be a major source of public fear. Through fear, terrorism has far-reaching implications for public governance.

One of the defining issues of our age, terrorism frequently makes headlines as governments, private businesses, and ordinary citizens find themselves at risk or under attack. But what is the nature of this threat, and what can be done about it?

This book contextualizes the use of terror as part of wider movements of political contention, demonstrating that terroristic innovation occurs as part of wider historical processes rather than in a vacuum.

Can conspiracy constructions explain for hatred of the system? And if so, should conspiracy constructions be considered to be a risk in terms of national security?

Perspectives on Terrorism (PT), the peer-reviewed online journal of the Terrorism Research Initiative (TRI) and the Institute of Security and Global Affairs (ISGA), is published six times per year by the Editorial Team with the help of members of the Editorial Board and the journal’s…

Promotor: F.S. de Boer Co-promotor: P. T. de Gouw

Our courses are aimed at higher educated professionals, starters, experienced professionals and managers. You can choose from day-long Masterclasses, multi-day courses and an intensive one-year program. Our English courses about Terrorism, Law, Safety and Security are listed below.

In December 2014, Leiden University’s Institute of Security and Global Affairs with the Australian National University’s Asia-Pacific College of Diplomacy and the International Centre for Counter-Terrorism, commenced a research project to assess how (temporary) military interventions can best prepare…

Jeanine de Roy van Zuijdewijn, PhD candidate at ISGA, explained the dilemma countries face in the aftermath of terror attacks.

A cautious response to a crisis or terrorist act avoids the creation of a culture of fear. This is another way to reduce our vulnerability to terrorism.

This paper investigates possible convergence of issue salience of terrorism among citizens within the European Union for ten jihadist attacks in the period 2015–2017 using Eurobarometer survey data.

This research paper was requested by the European Parliament's Committee on Civil Liberties, Justice and Home Affairs. It was published by the International Centre for Counter-Terrorism (ICCT) in The Hague. Leiden University is one of the participating institutes in this publication and our researcher…

This article written by Marieke Liem & Alexander Kamprad investigates the relationship between terrorism and interpersonal violence. They conducted cross-national analyses on the effects of terrorism mortality rates on homicide rates. Results showed that terrorism appears to be robustly and positively…

In recent years, the use of primary data in terrorism research has increased. In order to maximise the benefits of this trend, we want to encourage terrorism scholars to implement open science practices more systematically. This article therefore presents different avenues towards open and reproducible…

Terrorist attacks are not an end in themselves, but a means of creating unrest and fear. Terrorism policies and research should focus more on managing fear and social unrest.

Few events have influenced our global order as intensely as the events of September 11, 2001.

With 16 research institutions and more than 120 individual scholars from more than 30 countries in its ranks, the Terrorism Research Initiative (TRI) constitutes one of the largest research consortia in the field of Terrorism Studies.

An interview with Assistant Secretary General for Emerging Security Challenges David van Weel, and NATO Secretary General’s Special Representative for Women, Peace and Security (WPS) Clare Hutchinson

Political scientist Nicolas Blarel (Leiden University) analsyses how non-state actors can (directly or directly) attempt to provoke conditions for a crisis between state actors that have nuclear capabilities. He argues that there is an urgent but complicated and understudied task to understand and manage…

This collection includes six short policy-focused contributions exploring how legislation and policy on counter cyber terrorism unfold at the national level in the United States, the United Kingdom, China, Russia, France, and at the regional level of the European Union.

Perspectives on Terrorism 2016

What should policymakers and politicians do to prevent violent extremism? What are the greatest risks posed by the radical left and right? How do ideological media publications that terrorists assemble before attacks, may help to counter extremist narratives? About 30 professionals from all over the…

Self-censorship violates principles of a free society but few people want to take the role of the martyr.

Preventing terrorism before it happens seems like an idea no one would disagree to. But is it possible? How do counter-radicalisation policies look like? And are there dangers of unintended consequences? Francesco Ragazzi, Assistant Professor at Leiden University’s Institute of Political Science, has…

How have British, Dutch, and German security services dealt with political violence and terrorism since the late 1960s; to what extent did they consider these new phenomena as a task and how have they developed activities in order to counter these security threats?

These three repors are part of a research project that assesses how military interventions can best prepare the ground for an effective long-term counter-terrorism policy. Three different cases have been studied, and they have each provided the input for the policy relevant recommendations that are…

The ‘Community Resilience Fund’, a programme of the Canadian federal government, approved a research grant for Dr. Bart Schuurman of the Institute of Security and Global Affairs.

Comparing terrorist attacks with falling off a step ladder is absurd, writes Jeanine de Roy van Zuijdewijn in NRC Handelsblad on 27 September 2017.

Within the domain of health there can clearly be seen some new developments, for example e-healthcare solutions, which change the health landscape. However, in many African countries health care and public health are not sufficient enough.

This August, the second edition of the Advanced Summer Programme

The book addresses the question “How and why do people become involved in European homegrown jihadism?

Identifying the gaps in the legal framework for EU activities in the maritime security domain, and specifically in the areas of combating piracy, human smuggling or trafficking and drug trafficking.

Jeanine de Roy van Zuijdewijn teaches the masterclass terrorism 2018 together with Edwin Bakker. Read the interview here.

My research project aims to analyze reasons of the European Union’s (EU) inadequacy to develop a strong Common Security and Defense Policy (CSDP) with regard to the role of main EU member states, namely Germany and the United Kingdom (UK) and find the answer of how the EU overcome the CSDP question…

Acquiring and maintaining public support is frequently cited as an important requirement for governments fighting non-state actors. But how exactly can public support influence the course of counterterrorism campaigns and thereby contribute to an escalation or de-escalation of violence?