The UK’s approach to tackling modern slavery through the aid programme

Purpose, scope and rationale

Tackling modern slavery is an important new commitment for the UK aid programme, reinforced by high-level policy statements and an undertaking to spend £200 million of UK aid funds to address it. The purpose of this review is to assess how well responsible departments of the UK government have done in assembling an evidence base and developing a relevant portfolio of work to tackle this complex global challenge.

The review will cover modern slavery programming funded by the UK aid programme and related influencing activities since November 2014, when the UK’s first Modern Slavery Strategy was launched. We will explore how the UK’s approach and programming have evolved since their inception, and how well the government measures its performance against its objectives. The review will cover:

The UK government’s use of, and contribution to, the evidence base on modern slavery to inform sound
investments in current and future programming.

  • Dedicated modern slavery programmes and other programming that the government identifies as having
    a modern slavery element, focusing on:
  • The relevance of programme design;
  • The use and strength of evidence bases to inform programme design and assessment of programme

    • The quality of design and delivery, with the appropriate participation of the main stakeholders including survivors and other people expected to benefit, in design, implementation, and monitoring and evaluation.
    • The coherence, co-ordination and appropriate oversight of the UK government’s approach across the responsible departments.
    • The UK’s influencing work with other donors, multilateral partners and developing countries in promoting effective international cooperation on modern slavery.

The Independent Commission for Aid Impact (ICAI) has decided to undertake a review of the UK’s effort to tackle modern slavery through the aid programme because of the scale and importance of the issue, the severity of the suffering that it causes and the strong public commitment that the UK has made to addressing it. Ending modern slavery, both at home and abroad, has become a significant priority for the UK government, particularly since the adoption of the Modern Slavery Act 2015. The Sustainable Development Goals (SDGs) include a commitment to eradicating forced labour, modern slavery and human trafficking under Target 8.7. SDG 5 on gender equality, SDG 16 on peace, justice and strong institutions, and SDG Target 10.7 on migration are also relevant.

This is a relatively young portfolio, with most of the programming initiated in 2018. As this is an area where evidence on the nature and scale of the problem, and what works in tackling it, is still emerging, ICAI has an opportunity to assess how well the UK has assembled an evidence base and developed a portfolio of work that reflects the nature of the global challenge.


Modern slavery is an umbrella term encompassing slavery, forced labour, human trafficking, the worst forms of child labour and sexual exploitation, although these are distinct concepts covered by different international laws and conventions. Modern slavery occurs in a wide range of industries in the private sector, as well as through state-imposed forced labour. Children are considered a specific vulnerable population for forced labour. Forced marriage has recently been included as a sub-category of modern slavery by the International Labour Organisation.

Across its various forms, modern slavery involves fundamental abuses of human rights, depriving people of freedom and control over their lives, and often subjecting them to extreme suffering. Measuring the numbers of people subjected to modern slavery is very difficult. It is estimated that 40 million people are victims of modern slavery around the world, with 13,000 victims currently living in the UK, although some estimates for the UK are much higher. Former Prime Minister Theresa May described modern slavery as a “global epidemic”, the scale of which is “frightening to behold”.

The UK has sought to play a leading role internationally in tackling modern slavery. This has included a commitment to spending £200 million of aid to address modern slavery and sponsoring the 2017 international Call to Action to End Forced Labour, Modern Slavery and Human Trafficking, which has been endorsed by more than 90 governments. Modern slavery involves both cross-border and domestic challenges that need to be addressed in both source and destination locations and along often extended trafficking routes. It requires action not just by governments, but also by the private sector, which has a major responsibility to address modern slavery issues in its global supply chains. Aid has an important role to play in ending modern slavery, including commissioning research, funding programmes in developing countries and supporting legal and policy reform, and promoting effective international cooperation. However, it can only address part of the challenge. Action to tackle modern slavery within the UK is largely out of the scope of our review; however, the way in which the UK government works with the private sector to address modern slavery in developing countries will be a focus area.

Combating modern slavery at the international level is a cross-Whitehall effort. The Department for International Development (DFID), the Home Office and the Foreign and Commonwealth Office (FCO) are all involved in delivering the cross-government Modern Slavery Strategy, which addresses modern slavery both in the UK and around the world.

DFID has identified £199.5 million of its aid funds being deployed to tackle modern slavery,10 including a £20 million contribution to the multi-donor Global Fund to End Modern Slavery, matching a US commitment.11 The Home Office is contributing £33.5 million over a five-year period through the Modern Slavery Fund, including £11 million to a Modern Slavery Innovation Fund that invests in new and innovative projects designed to increase the knowledge and evidence base needed to tackle modern slavery internationally. The FCO has committed approximately £1.2 million, primarily through its International Programmes.

UK government-funded projects are focused on “reducing vulnerability to exploitation, addressing the permissive environments that enable the criminality of modern slavery to thrive, and supporting business to employ innovative approaches to eradicate exploitation in their supply chains”. An analysis of the portfolio on the basis of self-declaration by government departments suggests that there are 83 projects in the portfolio categorised in Table 1.

Table 1: The modern slavery portfolio of programmes

Department Fund/Programme Number of
Budget (£ million)
Home Office Modern Slavery Fund (MSF)
Home Office Modern Slavery Innovation Fund (MSIF) 18 10.9
Home Office Commonwealth Security Programme 22.4
FCO International Programmes 18 1.2
DFID UK Aid Direct Fund 5 4.0
DFID Country and central programmes 24 195.5
Total 83 224.6

Most of the programming focuses on South Asia, East Asia and sub-Saharan Africa, alongside regional and global programmes.

Review questions

The review questions, built around the evaluation criteria of Learning, Relevance and Effectiveness, are as follows.

Review criteria
and questions
How well has the UK government built and applied the evidence base in support of its modern slavery work• How well have the responsible departments identified data and evidence
gaps, and established suitable research, data collection, pilot programmes and evaluation approaches to address them?
• How well are knowledge and lessons learned being captured and disseminated to inform the UK and global response to modern slavery?
• How well has the UK government drawn on international experience and approaches to addressing modern slavery in designing its influencing work?
How well has the UK government gone about building a relevant, strategic,coordinated and credible portfolio of modern slavery programmes and influencing activities?• How well has the UK government defined the modern slavery problem and how well do its priorities within the modern slavery work reflect the nature and scale of the elements of the modern slavery challenge?
• How well does the UK government draw on the voices of those expected to benefit, including victims and survivors of modern slavery, in designing and delivering its response and in assessing the effectiveness of its interventions?
• How well does the UK government set its priorities within this portfolio to determine which channels it works through, including the private sector, and which partner countries it works with?
• How well does the approach and programming reflect the available evidence on what works?
• How coherent is the portfolio and approach across a) responsible departments; b) with other areas of UK aid; and c) relevant multilateral organisations?
How well is the modern slavery portfolio delivering results and value for money?• How well is the portfolio managed and executed?
• How well is the portfolio delivering its intended results and seeking to maximise value for money?
• How effectively is the UK government’s work on international modern slavery coordinated across government departments and with other donors?


This review will examine the progress that the UK has made in turning the relatively recent UK government commitment to addressing modern slavery into a credible portfolio of research, innovation, programming and appropriate programmatic evaluations. It will focus on the early stages of the results chain, including the foundational evidence to inform programming decisions, relevance and quality of programme design, with a particular interest in how the government commissions, accesses and uses research to fill data gaps, makes investment decisions and moves from designing and piloting new initiatives to programming at scale.

The methodology will review the current literature on modern slavery and assess the evolution of the UK government’s strategies and theories of change against the available evidence and the strength of the evidence. It will explore UK government approaches at country level and a sample of programmes in more depth, through desk reviews and country case studies, to identify strengths and weaknesses in the government’s response that can inform learning. The methodology will also include an approach to assessing the effectiveness of the UK government’s international influencing. Given the early stage of implementation of most programmes in the portfolio, the methodology will not look systematically at impact and value for money, although it will capture any evidence on emerging approaches to measuring results, impact and value for money.

Figure 1: Methodology


The methodology will have the following components:

Literature review: We will conduct a brief review of the literature on modern slavery. Drawing on existing syntheses where available, the literature review will provide a concise summary of key issues and conclusions emerging from both academic and grey literature. It will focus on the state of knowledge and the quality of evidence related to the review questions on learning and relevance. The key topic areas for the literature review will include:

  • Definitions and theories of change for addressing modern slavery.
  • Current evidence to inform programming investments, such as determinants to inform design and targeting of interventions.
  • Availability and quality of evidence on what works in addressing modern slavery.
  • Identifying areas of success and common obstacles in programming on modern slavery (including the assessment of the quality of the evidence).
  • Assessing the relevance of the international policy and legal environment to ending modern slavery.

Strategy review: We will conduct a review of the UK government’s strategy and approach to addressing modern slavery. This will include assessment of strategy papers, guidance, theoretical and evidentiary bases for interventions and theories of change, to determine whether they are internally coherent and reflect the available evidence to inform interventions identified in the literature review. In addition to document reviews, this will include key stakeholder interviews with the responsible UK government staff and collecting feedback from external stakeholders, including international organisations, UK non-governmental organisations (NGOs) and academic experts active in the area. We will review the government structures for managing the programme, in particular the cross-departmental structures, and whether each department is contributing based on its special expertise and capacity.

Influencing review: We will assess the strategies and effectiveness of the UK government’s attempts to influence action on modern slavery at the international and national levels, to answer our question on influencing under learning and relevance. We will also identify influencing activities within our desk reviews and country case studies. In our two country case studies, we will assess the UK’s contribution to strengthening national laws and policies on modern slavery. We will assess the achievements of UK influencing at the international level, including the development of partnerships, securing policy commitments and leveraging financial resources. A particular focus will be on the Call to Action, launched by the UK in September 2017, and its follow up, and the inclusion of modern slavery in the SDGs. As part of this work we will review the approaches of some other donor governments who have been prominent in modern slavery work to understand how their approaches align with, or differ from, that of the UK, and to identify their reasons for endorsing, or declining to endorse, the Call to Action.

Private sector review: We will assess the effectiveness of the UK government’s work with and through the private sector on modern slavery, where funded by the aid programme, to tackle modern slavery in global supply chains. This will include reviews of any relevant strategies, theories of change and conceptual frameworks that have been developed for the role of the private sector in modern slavery work and how they have evolved. We will undertake desk reviews on a sample of projects with private sector elements, and will review programming on labour recruitment, labour inspections, worker rights and survivor services where present. We will assess the partnerships developed by the UK government with companies, business associations and representative bodies to take this work forward, and the action that has been taken as a result of these. Eliminating modern slavery from private sector supply chains requires private sector action, and an important part of the UK government strategy should be to promote and complement this action.

Key informant interviews and focus groups: Initial interviews will be held with thought leaders to provide context for the review and identify lines of enquiry. This will be followed up with interviews with UK government staff, partner governments, international  rganisations and implementing agencies to understand the key challenges faced and perceived in achieving the UK’s objectives on modern slavery. Focus groups will be held with civil society, the private sector, and survivors and other people expected to benefit in our case study countries, allowing these important voices to be included in the review and to address our review questions on relevance and effectiveness.

Desk reviews: We will carry out desk reviews of a sample of the UK government’s programmes, covering the modern slavery funds and programmes managed by each of the three departments. The desk reviews will assess how well the UK government’s guidance, current evidence and theories of change have been translated into programme designs. They will examine whether business cases make proper use of the available evidence, and draw on adequate feedback from people expected to benefit and contextual analysis. The reviews will assess how each programme deals with evidence gaps in the country context through research and piloting, and the strategy for moving from design and programme development piloting to full-scale programming. The desk reviews will be based on programme documentation obtained from the responsible departments, including business cases, annual reviews and any evaluations undertaken, and telephone interviews with a small number of key stakeholders. The findings of the desk reviews will then be analysed to identify recurrent patterns, including strengths and weaknesses in the programming approach.

Country case studies: We will carry out case studies of the UK’s modern slavery approach in two countries, Nigeria and Bangladesh. We will conduct one-week visits to each country to view programme sites and to undertake interviews and focus groups. The case studies will enable us to assess how modern slavery is integrated across a country programme and how well modern slavery programmes interact with other sectoral programmes, including on governance and livelihoods. We will examine a selection of individual modern slavery programmes in more depth to test hypotheses derived from the literature, portfolio and desk reviews. We will explore how the responsible departments identify entry points for programming, how they interact with national stakeholders in government and civil society, and how they engage people expected to benefit – including victims and survivors – in the design, delivery and monitoring of programmes. Focus groups with survivors and other people expected to benefit will be undertaken in each country. Key issues for the case studies will be whether the scale and intensity of programming is commensurate with UK government objectives; and how the UK government plans to ensure that intervention designs are robust and evidence-driven, and to move from intervention development, adaptation and piloting to rigorous testing and evaluation of innovative activities and, finally, to delivery at scale.

Survivor voice: It is important that the review incorporates the voices of survivors and other individuals who have been recipients of UK support. We will use a variety of ethical and safe methods to incorporate survivor voice into our work, and to assess how well UK modern slavery initiatives reflect the needs and priorities of people expected to benefit from UK government support. As survivors represent a vulnerable group, our research will involve strict research protocols to minimise any risk of harm or distress through our engagement. The major elements of survivor consultation in this review are:

1) Desk reviews: We will assess whether there was evidence to inform the design, delivery and monitoring arrangements of the programmes and how they have meaningfully incorporated perspectives of survivors, informed stakeholders and local contextual constraints and opportunities.

2) Country case studies: Our approach to consultation in our case study countries will include:

  • Primary data collection directly through focus groups from people expected to benefit, including
    prospective and returnee labour migrants, victims and survivors;
  • Individual interviews with victims and survivors who are advocates and organisers of survivor groups;
  • Key stakeholder interviews with frontline agencies and organisations working with victims and

We will also undertake individual interviews with survivors who are confident and comfortable to speak. We will be supported in our research and analysis by local consultants in each country.

3) UK stakeholder interviews: We will undertake interviews with civil society organisations that advocate for the rights of victims and  survivors, and frontline agencies, including the Survivor Alliance, that work directly with survivors. We will also seek to organise a focus group with UK-based victims and survivors. 4) Secondary data: A unique and innovative feature of this review is our proposal to mine a major survivor testimony database for relevant narratives. ‘VOICES: Narratives by Survivors of Modern Slavery’ is the world’s largest database of survivor testimonies, managed by the Rights Lab at the University of Nottingham.16 There are limits on the coverage and timeliness of these stories, but this analysis will allow us to gain a broader understanding of the nature of the modern slavery challenges in our case study countries and beyond. We will use this testimony to provide context on the impact of modern slavery on victims and survivors, their families and communities.

These interlocking components of the methodology will provide a high level of triangulation of data to provide robust answers to our review questions. The literature review will be undertaken early in the process and will help to generate hypotheses and key lines of enquiry to pursue through the other elements of the review, as well as providing a basis for assessing the UK’s contributions to the evidence base. The desk reviews will cover a broad sample of the UK’s modern slavery programming, to identify patterns in performance; while the country case studies will enable us to explore how well the responsible departments respond to practical challenges in complex national contexts. The focus groups with civil society, the private sector, survivors and other people expected to benefit will provide additional perspectives on the relevance and effectiveness of the UK government’s work.



Sampling approach

The Home Office, DFID and the FCO have provided us with a list of all funds and programmes with a significant modern slavery element that have been active since November 2014. The portfolio includes modern slavery projects within five funds:

  • The Home Office manages two funds dedicated to modern slavery: the Modern Slavery Fund and the Modern Slavery Innovation Fund. The Home Office also manages two modern slavery projects within the Commonwealth Security Programme of the Commonwealth 2018–2020 Fund.
  • DFID funds some modern slavery work by NGOs through the UK Aid Direct mechanism, which ICAI reviewed in 2019.
  • The FCO supports some modern slavery work within its International Programmes Fund.

In addition, DFID has identified 24 bilateral and centrally-managed programmes that include a significant modern slavery element. This yields a total of 83 projects across the three departments, with combined expenditure commitments on modern slavery of £224.6 million.

There are variations in the size of projects funded by aid across departments. The DFID programmes in the portfolio spend an average of £6.8 million on modern slavery, while the Home Office projects average £660,000 and the FCO projects just £70,000. Over 90% of programmes are in Asia and sub-Saharan Africa. There are also a number of programmes that work at a global level, including in support of the UK’s global influencing objectives on modern slavery.

To address the issues raised in our review questions, we have developed a sampling approach that:

  • Looks broadly across programmes with learning, piloting and evidence-generation objectives to enable us to form an overall view of the quality of the learning approach;
  • Covers a broad cross-section of interventions by type, including which aspect or sector of modern slavery is being addressed, and by what means;
  • Covers a sufficient number of projects by each of the three spending departments, with a particular focus on the design and management of the two Home Office modern slavery funds;
  • Looks closely at any projects that support the UK’s global influencing agenda on modern slavery.

Our sample is summarised in Figure 2.

Figure 2: Overview of desk review sample

Overall, the sample will cover £103 million of the UK’s planned aid expenditure on modern slavery, or 46% of the overall portfolio by value. The smaller size of some programmes allows a greater proportion of these categories to be covered by our desk reviews.

Our two case study countries were selected in order to provide an opportunity to assess:

  • Programming in both Africa and Asia;
  • Programmes funded by each of the three departments;
  • Programmes focused on addressing human trafficking to the UK at source;
  • Programmes focused on modern slavery issues within developing countries.

The two countries with a substantial level of UK modern slavery programming that best met these criteria were Nigeria and Bangladesh.

Limitations to the methodology

There is no globally agreed definition of ‘modern slavery’. The experiences of people affected are diverse, and some stakeholders question this way of framing the issue. UK aid investments on modern slavery address a variety of challenges, including human trafficking, forced labour, child labour, sexual exploitation and domestic servitude. The portfolio is therefore diverse, making it difficult to identify a representative sample of activities to review or to generalise findings to the portfolio as a whole.

Most of the portfolio is relatively recent, with many of the programmes launched in 2018 and therefore still at an early stage of  implementation. There are therefore limited data available at this stage on results achieved, which may require us to qualify our findings on effectiveness. Most programmes have not been evaluated, and it will therefore be difficult to attribute changes to the intervention, rather than chance, time or other factors. There may also be limited data on evidence that informed the investment decisions and programming designs, but these gaps and shortcomings will be noted.

There are methodological challenges associated with reviewing the UK’s influencing work on modern slavery. In some cases, we will need to infer the UK government’s objectives from public statements, interviews or internal documentation. Furthermore, many developing countries are reluctant to acknowledge the existence of a modern slavery challenge affecting their citizens, giving rise to political sensitivities. This may hamper our evidence collection on the UK’s influencing work, and may mean that not all the evidence we collect can be included in the final report.

Research protocols and safeguarding

ICAI wishes to incorporate the survivor voice, to test whether the UK’s efforts on modern slavery are consistent with their needs and priorities. We therefore propose to conduct focus groups with individuals who have participated in UK programmes (including victims, survivors, migrants, returnees and at-risk groups) in our two case study countries.

When engaging with potentially vulnerable individuals, including minors, we will follow a set of strict research protocols designed to minimise the risk of distress or harm to participants. The engagement will be led by a team member experienced in conducting research with children and vulnerable individuals, and specialists in sexual exploitation, abuse and harassment, and associated safeguarding requirements. The team will also be supported by national experts able to bridge language and cultural differences. Focus groups will be held in appropriate spaces, where participants feel safe and able to speak in confidence. The research will focus on participants’ experience with UK aid interventions, rather than their experience of modern slavery. The dialogue will be conducted sensitively, and participants will be advised of their right to end their participation at any time. The team will be alert to any signs of distress, and will be in a position to refer individuals to appropriate support services, if needed.

We will obtain the informed consent of participants, following written or oral explanations of the purpose of the research. In the case of minors, there will be an enhanced consent process to include parental consent. We will respect the confidentiality of information collected during the research. Information on the identity of participants will be kept strictly confidential and separate from our interview notes. Information from participants will only be used in an anonymised form in reporting so that it cannot be traced back to specific individuals or locations.

Risk management

Table 3: Risks and mitigation measures

Mitigation and management actions
Consultation with survivors of modern
slavery causes distress or discomfort.
We will ensure appropriate design of consultations and robust
protocols and guidance for interaction with victims and
Some data needed for this review are
sensitive and restricted, including the UK
government strategy. Some countries are
unwilling to be characterised as having a
modern slavery problem. Publication of
details of the UK’s modern slavery efforts
may be harmful to diplomatic relations
and to ongoing programmes.
All team members will be security cleared and the ICAI
Secretariat will liaise with Home Office, DFID and FCO to agree
protocols on access to and use of restricted information.
Sensitivities of partner countries will be discussed with UK
government counterparts throughout the review. Sensitive
information will be anonymised, and our report will be reviewed
by the responsible departments to prevent inadvertent
disclosure of confidential or politically sensitive information.
Security risks limit team travel. The security situation can be volatile in our country case study
locations. We will be guided by security advice and amend
travel plans as required, with key gaps to be filled by telephone


Quality assurance

The review will be carried out under the guidance of ICAI Lead Commissioner Sir Hugh Bayley, with support from the ICAI Secretariat. The review will be subject to quality assurance by the Service Provider consortium. Both the methodology and the final report will be peer reviewed by Professor Cathy Zimmerman from the London School of Hygiene and Tropical Medicine. Professor Zimmerman is an expert in migration, health, human trafficking and gender-based violence.

Timing and deliverables

The review will take place over an 11-month period, starting from November 2019.

Table 4: Summary of the timeline for the review

Timing and deliverables
Inception • Approach paper: February 2020
Data collection • Country visits: March 2020
• Evidence pack: April 2020
• Emerging findings presentation: May 2020
Reporting • Final report: October 2020