Modern slavery remains one of the most challenging issues facing procurement and supply chain professionals today. Despite increased awareness and tougher legislation, forced labour, debt bondage, and human trafficking continue to permeate global supply chains—often hidden several tiers down from the organisations ultimately responsible for addressing them.

For UK businesses, the Modern Slavery Act 2015 brought statutory obligations into sharp focus. Section 54 requires commercial organisations with a turnover of £36 million or more to publish an annual statement describing the steps they've taken to ensure slavery and human trafficking aren't occurring in their own business or supply chains. Yet seven years on, compliance remains patchy and, more importantly, genuine impact on the ground has been limited.

Why Supply Chain Visibility Matters

The fundamental challenge with modern slavery is that it thrives on invisibility. Exploited workers are often found in the lower tiers of extended supply chains—the subcontractors, the farms supplying ingredients, the factories making components for components. A typical UK retailer might have direct relationships with a few hundred tier-one suppliers, but those suppliers in turn rely on thousands of tier-two and tier-three providers spread across multiple continents.

Without visibility into these deeper relationships, identifying modern slavery risks becomes essentially impossible. You cannot assess what you cannot see, and you certainly cannot address problems you don't know exist.

This is where supply chain mapping becomes critical. Building a picture of who supplies your suppliers—and who supplies them—transforms modern slavery from an abstract compliance requirement into a concrete risk management activity. It's not simple work, and it's never truly finished, but it's the foundation everything else depends upon.

Moving Beyond Tick-Box Compliance

Many organisations have responded to Modern Slavery Act requirements by adding clauses to supplier contracts and collecting annual declarations. Suppliers confirm they comply with modern slavery legislation, the paperwork gets filed, and everyone moves on. This approach satisfies the letter of the law but does precious little to identify or prevent actual exploitation.

Effective modern slavery risk management requires something more substantive. It starts with understanding which categories, geographies, and supplier types carry the highest inherent risks. Agriculture, construction, manufacturing, textiles, and domestic services consistently rank among the sectors most vulnerable to labour exploitation. Similarly, certain regions—where enforcement is weak, poverty is prevalent, or migrant workers form a significant proportion of the workforce—present elevated concerns.

Overlaying this risk framework onto your actual supply base allows you to prioritise efforts sensibly. Not every supplier relationship carries the same level of modern slavery risk, and treating them identically wastes resources while potentially missing genuine issues.

Due Diligence That Makes a Difference

For high-risk suppliers and categories, due diligence needs to go beyond self-certification questionnaires. Workers being exploited are rarely in a position to raise concerns through formal channels, and perpetrators have obvious incentives to hide what they're doing. Identifying modern slavery often requires more proactive investigation.

Worker voice mechanisms—confidential channels through which workers can report concerns without fear of retaliation—represent one valuable tool. These might include anonymous hotlines, worker interviews conducted by independent third parties, or engagement with local NGOs and trade unions who understand conditions on the ground.

Site audits remain important, but their limitations are well documented. Announced audits give bad actors time to prepare, and even unannounced visits capture only a snapshot in time. Audits work best as part of a broader programme that includes worker engagement, document verification, and ongoing monitoring for red flags.

Red Flags Worth Watching

Certain indicators should trigger closer scrutiny. Workers living in employer-provided accommodation with restricted freedom of movement. Excessive working hours with mandatory overtime. Wage deductions that leave workers perpetually in debt. Retention of identity documents by employers. Recruitment fees paid by workers rather than employers. Workers from vulnerable populations—migrants, refugees, those without legal status—in positions where exploitation is harder to detect.

None of these indicators definitively prove modern slavery, but each warrants investigation. Building these red flags into supplier monitoring—whether through questionnaire design, audit protocols, or worker feedback analysis—increases the chances of identifying problems before they escalate.

Collaboration Across the Industry

No single organisation can solve modern slavery alone. The supply chains that create exploitation span multiple buyers, multiple industries, and multiple jurisdictions. Addressing root causes requires collaborative action that goes beyond what any individual company can achieve.

Industry initiatives like the Responsible Labour Initiative, Sedex, and various sector-specific programmes provide frameworks for shared learning, joint auditing, and collective leverage. When multiple buyers make the same demands of shared suppliers, the business case for change becomes much more compelling.

Similarly, engagement with enforcement agencies, law enforcement, and civil society organisations brings expertise and resources that commercial organisations typically lack. Suspicious activity reports, information sharing about bad actors, and referrals to organisations supporting affected workers all contribute to a broader ecosystem of protection.

The Business Case

Beyond legal compliance and moral imperative, there's a growing business case for taking modern slavery seriously. Investors increasingly scrutinise ESG performance, and social factors—including labour practices—feature prominently in their assessments. Reputational damage from modern slavery revelations can be severe and long-lasting. And customers, particularly younger demographics, increasingly make purchasing decisions based on ethical considerations.

Perhaps more fundamentally, supply chains built on exploitation are inherently fragile. They depend on practices that, if discovered, create immediate disruption. Building more ethical supply chains isn't just the right thing to do—it's increasingly the smart thing to do.

The journey toward slavery-free supply chains is neither quick nor straightforward. But with proper visibility, risk-based prioritisation, meaningful due diligence, and collaborative action, genuine progress is possible. The question is no longer whether to act, but how quickly and how seriously.