The Arms Trade Treaty: Preventing Diversion Through End-Use and End-User Controls

Introduction

End-use and end-user control systems are key tools for preventing the diversion of conventional arms. When properly applied, such controls help to ensure that exported arms and ammunition are delivered solely to authorized end users and are not subject to misuse, diversion, or unauthorised retransfer.

However, these systems can fail to prevent diversion when:

• States do not authenticate end-use/r documentation, and forgeries are used to acquire export licences to divert arms
• States do not verify end-use/r documentation, with information missing or with details that should have prompted a thorough investigation of the proposed deal
• States that import arms lack procedures for oversight and control of those imports
• Importing states ignore assurances on end use or re-export, adherence to assurances is insufficiently monitored by the exporting state, and action is not taken when violations are reported
• High-ranking officials are willing – for financial or strategic gain – to provide authentic end-use/r documentation to facilitate diversion to embargoed entities either en route or via unauthorized re-export¹Michael Picard & Colby Goodman, Under the Radar: Corruption’s Role in Fueling Arms Diversion, Transparency International, 2025, https://ti-defence.org/wp-content/uploads/2025/04/Under-the-Radar-Corruptions-Role-in-Fueling-Arms-Diversion.pdf.

These are actual examples of the various ways in which inadequate or ineffective end-use/r control systems for conventional arms transfers have failed or been evaded to divert arms for unauthorized end use or to unauthorized end users. Such failures pose a global threat to peace, security and stability. Implementation of the Arms Trade Treaty (ATT) should help to strengthen national end-user control systems and enhance international cooperation and prevent the diversion of conventional arms.

At the multilateral level, the need to strengthen end-use/r control systems was first raised in the late 1990s. At that time, Panels and Groups of Experts assisting United Nations Security Council subsidiary bodies provided well-documented diversion cases to embargoed non-state and state entities.²United Nations, S/2002/115, pp. 5–23; United Nations, S/2203/223 Since then, states have worked in United Nations forums, as well as through regional and other multilateral frameworks, to increase the harmonization³The term “harmonization” as used in this Issue Brief is understood as meaning enhancing international cooperation; where possible, working towards agreement on common understandings; and aligning standards, in particular key elements to be contained in and end use/r documentation for ensuring effective end use/r controls. of end-use/r control systems to make them more effective in preventing the diversion of conventional arms and ammunition.⁴This Issue Brief uses the term “end-use/r control systems” in addition to the term “end-use/r certificate” since it covers not only the format and content of end-use/r documentation, but also the processes of certification, authentication and verification of such documentation and the documentation’s role in international cooperation to prevent diversion. For three decades, states have expressed their support for such efforts within the Security Council (as demonstrated in country/regional or thematic resolutions), the General Assembly, as well as under international conventional arms control frameworks such as the ATT.⁵For an earlier overview of these calls and relevant recommendations made and discussed by states at the multilateral level see, for example, UNIDIR Conventional Arms and Ammunition Programme, Examining Options to Enhance Common Understanding and Strengthen End Use and End User Control Systems to Address Conventional Arms Diversion (Geneva: UNIDIR, 2015), pp. 24–29, https://unidir.org/publication/examining-options-to-enhance-commonunderstanding-andstrengthen-end-use-and-end-user-control-systems-to-address-conventional-arms-diversion/.

The ATT obliges all states parties to take measures through their national control systems to prevent, detect, mitigate and address the diversion of international transfers of conventional arms. They should do this by assessing the risk that transferred arms will be diverted to unauthorized end uses or end users or to the illicit market.⁶ATT, Preamble, Article 1 and Article 11. See also Brian Wood and Paul Holtom, The Arms Trade Treaty: Measures to Prevent, Detect, Address and Eradicate the Diversion of Conventional Arms, ATT Issue Brief no. 2 (Geneva: Conflict ArmamentResearch, UNIDIR, Stimson Center, Small Arms Survey, 2020), https://doi.org/10.37559/CAAP/20/ASC/09. During meetings of the ATT’s Working Group on Effective Treaty Implementation (WGETI) between the fourth and eighth Conference of States (2018–22), states discussed the essential elements of an end-use/r control system, including documentation and related processes and procedures, and have exchanged national experiences and practices. As a result of these discussions, ATT stakeholders have prepared voluntary guidance to support the effective implementation of ATT Article 11 (diversion prevention) and related Treaty provisions. Nonetheless, there remain avenues to promote more effective use of end-use/r controls under the ATT framework.

Purpose of this ATT Issue Brief

This ATT Issue Brief outlines the different ways in which ineffective end-use/r controls – in particular, the use of documentation – facilitates the diversion of conventional arms. It identifies ways in which states may seek to strengthen existing systems in order to implement the ATT’s diversion-prevention and related provisions more effectively. Specifically, this brief is intended to inform discussions within the ATT WGETI’s Sub-Working Group on Exchange of National Implementation Practices, given its ongoing work on national import controls, and future deliberations on intersecting issues.

This is the sixth ATT Issue Brief prepared by the research consortium of UNIDIR, Conflict Armament Research (CAR) and the Stimson Center. It is part of a series that seeks to strengthen shared understanding on the impact of the ATT in addressing diversion and to identify effective measures and options to further promote effective policies and practices under the Treaty.

This ATT Issue Brief draws on extensive previous research by the consortium; relevant documents developed by ATT states parties to support effective treaty implementation; instruments and guidance documents developed by states at the regional level; and relevant publications by international, regional and nongovernmental organizations. It includes an analysis of relevant information contained in publicly available initial reports on ATT implementation from 70 states parties. In addition, it contains an analysis of 75 end-use/r documents.

This Issue Brief is structured as follows:

• Section 2 provides an introduction to end-use/r controls, with a particular focus on end-use/r documentation used by states in international conventional arms transfers.
• Section 3 presents cases of diversion that illustrate the challenges related to the effective use of end-use/r documentation, and related roles and responsibilities, in preventing diversion.
• Section 4 provides insights into the reported use of end-use/r controls, including documentation, by ATT states parties in their initial reports on implementing the Treaty.
• Finally, Section 5 provides some key options to strengthen end-use/r controls, in particular documentation, at the multilateral level. These could be pursued within the ATT framework to achieve the Treaty’s purpose and objectives of preventing arms diversion.

Notes

• 1
  Michael Picard & Colby Goodman, Under the Radar: Corruption’s Role in Fueling Arms Diversion, Transparency International, 2025, https://ti-defence.org/wp-content/uploads/2025/04/Under-the-Radar-Corruptions-Role-in-Fueling-Arms-Diversion.pdf.
• 2
  United Nations, S/2002/115, pp. 5–23; United Nations, S/2203/223
• 3
  The term “harmonization” as used in this Issue Brief is understood as meaning enhancing international cooperation; where possible, working towards agreement on common understandings; and aligning standards, in particular key elements to be contained in and end use/r documentation for ensuring effective end use/r controls.
• 4
  This Issue Brief uses the term “end-use/r control systems” in addition to the term “end-use/r certificate” since it covers not only the format and content of end-use/r documentation, but also the processes of certification, authentication and verification of such documentation and the documentation’s role in international cooperation to prevent diversion.
• 5
  For an earlier overview of these calls and relevant recommendations made and discussed by states at the multilateral level see, for example, UNIDIR Conventional Arms and Ammunition Programme, Examining Options to Enhance Common Understanding and Strengthen End Use and End User Control Systems to Address Conventional Arms Diversion (Geneva: UNIDIR, 2015), pp. 24–29, https://unidir.org/publication/examining-options-to-enhance-commonunderstanding-andstrengthen-end-use-and-end-user-control-systems-to-address-conventional-arms-diversion/.
• 6
  ATT, Preamble, Article 1 and Article 11. See also Brian Wood and Paul Holtom, The Arms Trade Treaty: Measures to Prevent, Detect, Address and Eradicate the Diversion of Conventional Arms, ATT Issue Brief no. 2 (Geneva: Conflict ArmamentResearch, UNIDIR, Stimson Center, Small Arms Survey, 2020), https://doi.org/10.37559/CAAP/20/ASC/09.