Modern Slavery Prevalence Methods Scoping Review 

Rights Lab project lead: Todd Landman 
Funder: UK Independent Anti-Slavery Commissioner 
Duration: November 2024-March 2025
Programme: Measurement and Geographies 

The estimation of UK modern slavery prevalence has varied between 10,000 and 136,000; numbers produced using different methods and different data sources. The UK Independent Anti-Slavery Commissioner (IASC), Eleanor Lyons, has argued that there is an urgent need for a new, robust UK prevalence estimate to provide much needed evidence for formulating modern slavery law and policy, made particularly pressing in the context of a new government and its intention to develop a revised Modern Slavery Strategy (as recently recommended by the Home Affairs Select Committee and US Department of State). To know how to do this requires a scoping and methods development stage. 

This study completed a scoping review of all available data sources and methods of analysis with a view to developing an estimation protocol of UK modern slavery prevalence. The research mapped all relevant primary and secondary data sources; assessed the strengths and weaknesses of different prevalence estimation methods; surveyed a large number of stakeholders on the perceived importance and practical application of a revised prevalence estimate; and summarised this evidence to provide key findings and policy, delivery and research recommendations.