Discussions at this year’s GreenBiz conference consistently highlighted the business rationale for sustainability. Executives frequently emphasized that initiatives to lower emissions were simultaneously minimizing waste, decreasing expenses, and providing lasting efficiency improvements.

This is a completely sensible argument. However, it is also far more restrained than the sustainability spirit of recent years, when businesses declared a green overhaul to be the major growth narrative of this century.

To some extent, this represented an essential correction. During the peak of ESG investing, vast sums of money were allocated with expectations of huge profits but lacking a definitive strategy. Becoming more specific is crucial, yet by centering the business argument for climate action on efficiency, companies may forfeit the enthusiasm—and investment—associated with expansion.

In Phoenix, sustainability leaders grappled with defining their purpose in a climate of governmental resistance to climate action and the public’s focus on different concerns. Numerous executives described how their roles have shifted towards ensuring adherence to a growing number of regulations. Even with a shift in policy from the U.S. federal government, other nations and certain U.S. states are advancing various climate rules. Some voiced worries about downsizing sustainability departments as chief executives focused on other areas. Nearly all reported sustaining climate initiatives by identifying methods to reduce corporate spending.

Pursuing efficiencies is a fundamental part of decarbonization. Yet, as professionals in the field contemplate their future roles, they must determine how to position climate and sustainability as central to compelling growth, rather than just incremental efficiency improvements.

The on-stage debate at the conference over the potential irrelevance of the chief sustainability officer (CSO) role starkly illustrated the existential doubts facing these executives. The core of the debate was not the importance of sustainability, which was assumed. Rather, it focused on whether sustainability is best housed in a dedicated department or if it should be integrated into the responsibilities of all departments, from finance to strategy.

Based on the audience’s reaction, the side arguing for the continued relevance of CSOs won decisively. The most persuasive point, in my view, was that a dedicated individual is needed to advocate for sustainability across the organization. “The CSO serves as a compass,” stated Olubamise Onabanjo, manager of sustainability reporting at E.L.F. Beauty, during the debate.

But what direction is that compass indicating?

Many executives are confronting a difficult reality privately: the commercial justification for large, growth-focused investments is often not immediately obvious. A January survey of C-suite leaders by The Conference Board revealed that while most global CEOs still claim to prioritize sustainability, their primary methods are waste reduction and efficiency. Initiatives like greening the supply chain and developing green products are lesser priorities.

Jesper Brodin, the former CEO of Ingka Group, IKEA’s main operator, noted this month that the efficiency gains from sustainability investments are evident across various sectors. “It has great impact on your cost side,” he explained. “The business upside of climate smart transformation depends a little bit on which type of business you are.”

Notable conversations in Phoenix involved executives who contend that sustainability can fuel growth and innovation. Leaders from consumer-facing companies cited remarkable data from Amazon, showing that products labeled as “Climate Pledge Friendly” experienced a 14% sales increase right after receiving the designation. This demonstrates that sustainability investments can directly stimulate business expansion.

The energy sector offers a prime example of a decarbonization innovation evolving into a growth driver. Decades ago, the argument for solar power and battery storage relied heavily on uncertain regulatory risks and energy security needs. The journey has been more complex than predicted, but these technologies are now yielding returns as their costs decline and electricity demand rises.

In practice, large corporations tend to avoid risk. Investments require a reasonable assurance of a return. However, a focus on efficiency alone may be insufficient to restore sustainability to the forefront of business trends.

To receive this story in your inbox, subscribe to the TIME CO2 Leadership Report newsletter .

This story is supported by a partnership with and Journalism Funding Partners. TIME is solely responsible for the content.