On 27 August, UNIDIR, Conflict Armament Research and the Stimson Center, with support from the United Kingdom, launched a new initiative to assess progress towards the objectives of the Arms Trade Treaty (ATT). The partners presented the initiative at an interactive side event on the margins of the Twelfth Conference of States Parties to the Arms Trade Treaty (ATT CSP12) in Geneva.
Adopted in 2013, the ATT created global rules to regulate the international trade in conventional weapons and thereby prevent and eradicate their diversion to the illicit trade. The treaty ultimately aims to reduce human suffering and contribute to international peace, security and stability.
Across 2026 and 2027, UNIDIR and its partners are working to deliver the first comprehensive impact evaluation of the ATT. This evaluation will assess the treaty’s influence on national transfer control systems, efforts to counter diversion, and international cooperation to strengthen international security and reduce human suffering. The project aims to inform efforts to prepare and adopt the ATT’s first five-year strategy.
At the launch, the United Kingdom’s Ambassador to the Conference on Disarmament, David Riley, who will also serve as President of the next Conference of States Parties, underlined that impact evaluation represents a valuable tool in shaping a five-year ATT strategy, which will be a priority of the UK presidency.
The event centred on a discussion among gathered participants around three essential questions for the evaluation methodology:
- What impacts should be assessed?
- How to assess the ATT’s impact?
- How to attribute change and impact to the ATT?
What impacts should be assessed?
UNIDIR Associate Researcher Paula Soumaya Domit asked participants what impacts they felt the ATT should be having, with responses ranging from improved transparency in the arms trade to the prevention of gender-based violence. The initiative will examine the ATT’s impact in five areas related to the treaty’s object and purpose, ranked by participants as follows:
How to assess the ATT’s impact?
Turning from what to assess to how to assess it, Stimson Center Acting President and Chief Executive Officer Rachel Stohl asked participants what data to use for the impact evaluation. Some data sources, such as ATT initial and annual reports, are readily accessible. But others proposed by participants are either completely unavailable or are available only for a few States, as in the case of licence denials. Participants’ candid reflections on data collection challenges (see below) were particularly useful for the initiative’s assessment methodology.
How to attribute change and impact to the ATT?
Conflict Armament Research Head of Research Rob Hunter-Perkins asked participants to help the team credibly attribute observed changes to the ATT. Participants provided a long list of ways to demonstrate the ATT’s contribution to a particular outcome, some of which are shown below:
Two major challenges stand in the way of establishing clear causality between the ATT and the various impacts related to its object and purpose:
- The ATT’s effect is hard to isolate from that of other frameworks
The treaty sits within an overlapping set of regional and international frameworks that together recommend or require that States put in place a national transfer control system, establish a legal and regulatory framework, and conduct risk assessments before authorizing international arms transfers. Attributing any specific change to the ATT alone is therefore challenging. - Changes in human suffering are hard to measure and attribute
It is very difficult to determine whether human suffering is greater, smaller or the same as it would have been without the treaty, let alone if these changes can be attributed directly to national implementation of the treaty and application of its provisions. Nonetheless, many participants highlighted this as an important metric for evaluating the ATT’s impact.
The project team is now embarking on a pilot study to explore how best to minimize the impact of these challenges on the study’s results.
From pilot to full evaluation
The first phase of the initiative is a pilot study with ten States Parties, which will help to validate impact indicators and determine the feasibility of data collection.
Pilot study results will be shared on the margins of the ATT working group meetings for the Thirteenth Conference of States Parties in March 2027. The final evaluation study, meanwhile, will present the full methodology and results. These can then feed into efforts to develop a baseline for the five-year strategy, which will in turn facilitate better monitoring of its implementation.
The initiative aspires to show where the ATT is having a positive impact and to identify areas where more work is needed.
For more non-party States to come on board and spread the ATT’s benefits, we need clearer evidence of progress towards its core goal: a responsible international arms trade with minimal diversion risks that contributes to international peace, security, stability and sustainable development.