The term “modern slavery” has gained significant attention through its inclusion in British and Australian legislation as well as in the United Nations’ Sustainable Development Goal 8.7. However, as it is not yet consistently defined in international law (Boersma and Nolan, 2022), scholars and organizations engage with the concept using different definitions. One widely referenced definition of slavery in supply chains by Gold et. al (2015, p. 487) reads as follows:
“We define slavery in supply chains as the exploitation of a person who is deprived of individual liberty anywhere along the supply chain […] for the purpose of service provision or production.”
This definition was further refined for the purposes of the project, resulting in the following four key elements:
Why we use the term “modern slavery“
Using the term “modern slavery” has the potential to enrich debates for several reasons:
- Unifying function: The term helps bring coherence to otherwise fragmented concepts, highlighting shared features across diverse forms of severe exploitation. This makes it easier for actors such as NGOs and policymakers to operate within a common narrative framework.
- Conceptual flexibility for a comprehensive analysis: Its lack of a rigid legal definition allows the term to adapt to different contexts and capture a broad spectrum of exploitative practices, including those in grey areas along the continuum of exploitation.
- Political mobilization on a large scale: The concept foregrounds systemic abuses in global labour markets and can spur debates on structural reform as well as more comprehensive legislative initiatives. The UK’s Modern Slavery Act (2015) and Australia’s Modern Slavery Act (2018) illustrate how the umbrella term can be effectively incorporated into national legislation.
- Public awareness: With its strong moral resonance, the term serves as a powerful communication tool, enhancing public understanding of exploitative practices and increasing engagement with the issue.
(cf. International Labour Organization. (2015). Modern slavery: The concepts and their practical implications (Working Paper). https://www.ilo.org/publications/modern-slavery-concepts-and-their-practical-implications)
Common forms of modern slavery
Although modern slavery is not specifically defined in international law, it is commonly used as an umbrella term for various related legal concepts. These concepts are often used interchangeably due to significant overlaps, yet are conceptually distinct. They include, but are not limited to the following:
- Human trafficking: the recruitment, transportation, transfer, harbouring or receipt of people through force, fraud or deception, with the aim of exploiting them for profit.
- Forced labour: “all work or service which is exacted from any person under the menace of any penalty and for which the person has not offered himself or herself voluntarily” (ILO Forced Labour Convention, 1930, No. 29).
- Debt bondage: a person’s labour or services are pledged as security for the repayment of a debt or other obligation, often without any control over the terms or duration of repayment.
- Descent-based slavery: inherited forms of bondage in which individuals are born into slavery or servitude due to their lineage, caste, or social group.
- Sexual exploitation: practices such as sexual exploitation and abuse, forced prostitution, and the exploitation of children for the production of child sexual abuse material.
- Child slavery: the exploitation of children in slavery-like conditions, including forced labour and trafficking.
- Forced and early marriage: an individual is compelled to marry without their free and full consent, frequently affecting children.*
- Domestic servitude: forced labour in private households, typically characterised by restricted freedom of movement, and limited or no remuneration.
*Not classified as modern slavery in the UK
(cf. International Labour Organization. (n.d.). What is forced labour? https://www.ilo.org/topics/forced-labour-modern-slavery-and-trafficking-persons/what-forced-labour; Australian Government, Department of Home Affairs. (n.d.). Types of modern slavery. Modern Slavery in Australia. https://www.modernslavery.gov.au/about-modern-slavery/types-modern-slavery; Unseen UK. (n.d.). Types of modern slavery. Unseen. https://www.unseenuk.org/about-modern-slavery/types-of-modern-slavery/)
Slavery – today and in the past
One of the most significant periods in the history of slavery was the transatlantic slave trade, during which an estimated 10 to 12 million enslaved Africans were forcibly transported, primarily to the Americas, from the 16th to the 19th century. From 1807 onwards, the transatlantic slave trade was formally abolished by Britain and other countries. In this context, the 1926 Slavery Convention of the League of Nations defined slavery as “the status or condition of a person over whom any or all of the powers attaching to the right of ownership are exercised” (article 1.1).
(cf. Rawley, J. A., & Behrendt, S. D. (2005). The transatlantic slave trade: a history. U of Nebraska Press.)
Now, slavery is prohibited by law worldwide. However, it is not a thing of the past. Processes of modernization, globalization, and technical advancement have transformed global supply chains and created new opportunities for exploitation, such as online sexual exploitation, cyber scam centres, or transnational trafficking networks. In modern slavery, control is the contemporary parameter for ownership, exercised through violence, threats, deception, and psychological coercion.
Today, more people are living in conditions of slavery than at any other point in recorded history, affecting every region of the world. According to the International Labour Organization (2022), an estimated 49.6 million people were victims of modern slavery in 2021. Of these, 27.6 million were subjected to forced labour, while 22 million were trapped in forced marriage. Modern slavery is estimated to (criminally) generate more than $150 billion every year.
(cf. Allain J (ed) (2013) The legal understanding of slavery: From the historical to the contemporary. Oxford: Oxford University Press; data from International Labour Organization, Walk Free, & International Organization for Migration. (2022, September 12). Global estimates of modern slavery: Forced labour and forced marriage. International Labour Organization. https://www.ilo.org/publications/major-publications/global-estimates-modern-slavery-forced-labour-and-forced-marriage)
Critical reflection on the term “modern slavery“
Some academics have articulated critique regarding the concept of modern slavery:
- Risk of overgeneralization: Modern slavery might be too dynamic and multifaceted to fit under a single umbrella term.
- Susceptibility to political instrumentalization: The emotive strength of the term “slavery” can be strategically used in public or political discourse in ways that diverge from evidence‑based policy and oversimplify the complexities of contemporary labour abuses.
- Lack of definitional clarity: Unlike slavery, forced labour, or human trafficking, modern slavery has no formal legal definition, creating ambiguity and potential inconsistencies in policy design, implementation, and enforcement.
- Blurring structural versus criminal dimensions: As an overarching concept, it risks conflating individualized criminal acts with systemic, structurally embedded exploitation. This may lead to an overemphasis on crime control at the expense of addressing underlying socioeconomic and institutional drivers.
(cf. Mende, J. (2019). The Concept of Modern Slavery: Definition, Critique, and the Human Rights Frame. Hum Rights Rev 20, 229–248. https://doi.org/10.1007/s12142-018-0538-y)
References
- Allain, J. (Ed.). (2013). The legal understanding of slavery: From the historical to the contemporary. Oxford University Press.
- Australian Government, Department of Home Affairs. (n.d.). Types of modern slavery. Modern Slavery in Australia. https://www.modernslavery.gov.au/about-modern-slavery/types-modern-slavery
- Bales, K. (2012). Disposable people: New slavery in the global economy (Updated with a new preface). University of California Press.
- Caruana, R., Crane, A., Gold, S., & LeBaron, G. (2021). Modern slavery in business: The sad and sorry state of a non‐field. Business & Society, 60(2), 251–287. https://doi.org/10.1177/0007650320930417
- Christ, K. L., Burritt, R. L., & Schaltegger, S. (2020). Accounting for work conditions from modern slavery to decent work. Accounting, Auditing & Accountability Journal. https://doi.org/10.1108/AAAJ-05-2020-4587
- Crane, A. (2013). Modern slavery as a management practice: Exploring the conditions and capabilities for human exploitation. Academy of Management Review, 38(1), 49–69. https://doi.org/10.1108/AAAJ-05-2020-4587
(Hinweis: Der DOI im Original war falsch; offizieller DOI wäre → https://doi.org/10.5465/amr.2011.0145) - Gold, S., Trautrims, A., & Trodd, Z. (2015). Modern slavery challenges to supply chain management. Supply Chain Management: An International Journal, 20(5), 485–494. https://doi.org/10.1108/SCM-02-2015-0046
- International Labour Organization. (2015). Modern slavery: The concepts and their practical implications (Working Paper). https://www.ilo.org/publications/modern-slavery-concepts-and-their-practical-implications
- International Labour Organization. (2017). Global estimates of modern slavery: Forced labour and forced marriage. https://www.ilo.org/publications/global-estimates-modern-slavery-forced-labour-and-forced-marriage
- International Labour Organization. (n.d.). What is forced labour? https://www.ilo.org/topics/forced-labour-modern-slavery-and-trafficking-persons/what-forced-labour
- International Labour Organization, Walk Free, & International Organization for Migration. (2022). Global estimates of modern slavery: Forced labour and forced marriage. International Labour Organization. https://www.ilo.org/publications/major-publications/global-estimates-modern-slavery-forced-labour-and-forced-marriage
- Mende, J. (2019). The concept of modern slavery: Definition, critique, and the human rights frame. Human Rights Review, 20(2), 229–248. https://doi.org/10.1007/s12142-018-0538-y
- Nolan, J., & Boersma, M. (2019). Addressing modern slavery. UNSW Press. https://doi.org/10.1177/00221856211069238
(Hinweis: Der DOI verweist auf eine Buchrezension; das Buch selbst hat keinen DOI.) - Phillips, N. (2013). Unfree labour and adverse incorporation in the global economy: Comparative perspectives on Brazil and India. Economy and Society, 42(2), 171–196. https://doi.org/10.1080/03085147.2012.718630
- Rawley, J. A., & Behrendt, S. D. (2005). The transatlantic slave trade: A history. University of Nebraska Press.
- Strand, V., Lotfi, M., Flynn, A., & Walker, H. (2024). A systematic literature review of modern slavery in supply chain management: State of the art, framework development and research opportunities. Journal of Cleaner Production, 435, 140301. https://doi.org/10.1016/j.jclepro.2023.140301
- Such, E., Jaipaul, R., & Salway, S. (2020). Modern slavery in the UK: How should the health sector be responding? Journal of Public Health, 42(1), 216–220. https://doi.org/10.1093/pubmed/fdy217
- Szablewska, N., & Kubacki, K. (2023). Empirical business research on modern slavery in supply chains: A systematic review. Journal of Business Research, 164, 113988. https://doi.org/10.1016/j.jbusres.2023.113988
- Unseen UK. (n.d.). Types of modern slavery. https://www.unseenuk.org/about-modern-slavery/types-of-modern-slavery/