2025 in review – How the CSO role evolved

It wasn’t easy being a Chief Sustainability Officer (CSO) in 2025. Amid political backlash, economic pressure, regulatory recalibration and rapid technological change, sustainability leadership was tested not just on ambition, but on resilience, credibility, and organisational influence. The year revealed a role in transition: less about expansion and evangelism, more about endurance, integration, and strategic trade-offs.

From momentum to resilience

Much of the year was shaped by what many sustainability leaders openly described as a downturn. Political shifts, a cooling of sustainability hiring, and growing scrutiny of ESG spending created an environment where sustainability ambition was no longer assumed. CSOs were forced to operate in what some described as a “sustainability recession” – one marked by competition for capital, rising systemic risks, and heightened expectations to demonstrate value.

Yet this was not a simple retrenchment. While sustainability hiring has cooled compared to its peak, it remains far higher than pre-pandemic levels, suggesting a structural shift rather than a reversal. At the same time, UK firms expect to increase sustainability budgets by around 40% by 2030, indicating that long-term intent remains intact – even if short-term priorities are being rebalanced.

For many CSOs, the challenge in 2025 was therefore not whether sustainability still mattered, but how to sustain momentum through uncertainty.

Staying the course in a downturn

Few articulated this challenge more clearly than former IKEA CSO Pia Heidenmark Cook. Drawing on two decades of experience, she framed 2025 not as an anomaly but as part of a familiar cycle – one where sustainability periodically slips down corporate agendas before returning with greater force.

Her advice to CSOs was pragmatic: accept that some large, transformative projects may pause, but use the time to strengthen foundations. Regulatory baselines, she noted, are now far higher than in previous downturns, with mandatory sustainability disclosures expanding across Europe and globally. Compliance alone now provides CSOs with a powerful anchor inside organisations.

Beyond regulation, Heidenmark Cook emphasised two priorities: data and morale. Strong data systems, credible metrics, and supply chain visibility are not optional extras – they are the backbone of the sustainability business case. At the same time, she highlighted the emotional toll of the role, urging sustainability leaders to support their teams, find community, and remember that they are not alone. In her words, sustainability leadership is “a marathon, not a sprint”.

A role under emotional and strategic strain

If Heidenmark Cook focused on endurance, former Decathlon CSO Anna Turrell captured the emotional and systemic strain many CSOs felt in 2025. After stepping back from her role, Turrell described the year as an inflection point – not just for sustainability leaders, but for the economic system they operate within.

Unlike previous downturns, she argued, this moment feels different because multiple pressures are converging at once: post-Covid financial stress, supply chain disruption, geopolitical volatility, regulatory uncertainty, and the rapid adoption of AI. For CSOs, this created what she described as “corporate whiplash”, with sustainability teams often among the first to be cut or restructured.

Turrell was candid about the discomfort this creates – and about the need for leaders to lean into it. She warned that deprioritising sustainability is often a short-term reaction that simply defers costs into the future. Climate risk, she noted, does not recede because political attention shifts. The harder truth, in her view, is that sustainability is colliding with a system still fundamentally built around short-term financial incentives.

From influence to integration

One of the clearest evolutions of the CSO role in 2025 was its closer integration with finance. The CFO–CSO relationship increasingly emerged as one of the most critical alliances in the C-suite, shaping how sustainability is budgeted, measured, and prioritised.

This shift reflects a broader redefinition of the role. CSOs are no longer primarily advocates; they are translators between sustainability outcomes and financial decision-making. That requires fluency in capital allocation, risk management, and return on investment – and the ability to defend sustainability spend in increasingly competitive internal environments.

At the same time, the role is becoming more technically demanding. AI literacy moved firmly onto the CSO skills agenda in 2025, as sustainability leaders were expected to understand how data, automation, and AI tools could accelerate – or complicate – sustainability performance.

Talent, diversity, and credibility

This part year also exposed deeper questions about talent and representation. Studies highlighted persistent diversity challenges within the sustainability profession, raising concerns about whose voices shape corporate sustainability strategies. A lack of diverse leadership risks narrowing both perspective and effectiveness – particularly when sustainability strategies require deep engagement with communities, workers, and global supply chains.

In parallel, companies began rethinking how they attract, retain, and develop sustainability talent, recognising that burnout, role ambiguity, and unrealistic expectations are undermining long-term impact.

A quieter, tougher kind of leadership

By the end of 2025, the CSO role looked markedly different from just a few years earlier. It was less visible in corporate marketing, less insulated from political and economic pressure, and more deeply embedded in the mechanics of business decision-making.

Yet if the year stripped away some of the optimism that characterised earlier phases of corporate sustainability, it also revealed a more mature form of leadership. One grounded in data, regulatory reality, cross-functional influence, and the courage to speak uncomfortable truths.

As both Pia Heidenmark Cook and Anna Turrell made clear in different ways, sustainability leadership today is about staying power – holding course through uncertainty, preparing for the next upswing, and helping organisations adapt before external pressures remove the choice altogether.

In 2025, the CSO did not disappear. The role grew tougher, quieter, and more strategic – and, in many ways, more essential than ever.