The hidden control problem in external workforce sourcing

by Pete Davison and Greg Horgan

Most organisations have controls in place around their external workforce, often led through procurement frameworks such as preferred suppliers, approval processes, and managed service agreements. And yet the overall outcome often tells a different story: costs continue to drift, visibility remains limited, and risk accumulates.

These issues can result from control gaps within individual areas. But the more common – and yet less recognised – root cause is how these controls operate in isolation.

This is particularly evident in how external workforces are managed in transformation-heavy enterprises. External workforces – primarily Application, Development and Maintenance (ADAM), consultancy, and contingent labour – commonly underpin strategy delivery. In practice, they operate as a single delivery system, supporting the same programmes, funded through the same budgets, and influencing the same outcomes. Yet they are often treated as separate streams, governed by different policies, managed by different stakeholders, and contracted under inconsistent commercial structures. Over time, that disconnect erodes control.

Where the category model breaks down

The distinction between ADAM, consultancy, and contingent labour remains useful from a sourcing perspective. However, it is less effective as a structure for governing how that capability is used.

A single transformation programme may involve long-term ADAM providers maintaining core platforms, consulting teams shaping design and governance, and contingent specialists embedded within delivery. These roles are often commissioned at different points, through different channels, and under different commercial models, but ultimately contribute to the same delivery outcomes. Because they are governed separately, key control levers tend to evolve independently. 

Fragmentation erodes commercial leverage

Supply bases become fragmented, rate structures diverge, and cost escalation mechanisms compound unevenly across agreements. Competitive tension varies by category maturity, and visibility of the true, total cost remains limited.

Workforce visibility breaks down 

The impact extends beyond cost and into how delivery is structured. Externally sourced roles often operate alongside permanent employees for extended periods, becoming embedded within programme delivery. Without a consolidated view, it becomes difficult to assess how external resources are being used across the organisation, or how they complement internal capability. 

Risk accumulates across engagements 

External workforce models carry compliance and regulatory risk: worker misclassification, co-employment exposure, IR35 and equivalent regime breaches, permanent establishment tax exposure, payroll non-compliance, data privacy obligations and cross-border labour requirements.

When ADAM, consultancy and contingent labour are governed separately, these risks are not managed consistently. Controls are applied unevenly across engagement models, and accountability becomes fragmented.

Individually, these dynamics may seem manageable. But collectively, they become difficult to monitor and control, with fragmentation becoming a structural issue over time. At that point, the external workforce can no longer be managed as a set of adjacent categories but instead must be governed as a single portfolio – a core principle of a Strategic Workforce Management approach.

This raises the question: where does effective control actually begin?
 

The first strategic question: Should this demand exist externally at all? 

Organisations often approach control through sourcing, but it should begin earlier, with defining demand:

Should this demand exist at all? Can this requirement be fulfilled internally?

Organisations regularly default to external engagements out of urgency, habit, or demand within individual programme budgets. Yet every externally fulfilled role carries a host of implications, ranging from margin premiums, onboarding friction, IP leakage risk, lost opportunities to develop internal capability, to increased governance burden.

A more mature approach includes a structured triage process: (i) assessing opportunities for internal redeployment; (ii) validating capability gaps; and (iii) building a clear business case for external engagement. Identifying and avoiding unnecessary demand is the most effective form of cost optimisation.