At Earth Action (EA), we surround ourselves with experts who are not only leaders in their fields but also deeply aligned with our mission to drive meaningful impact. Our network of collaborators isn’t just a roster of names — it’s a community. These are the people we call when we need to challenge our own thinking, co-create new approaches, deliver innovative solutions to our clients, or think about accounting for impact.
One of those experts is Samuel Vionnet, founder of Valuing Impact, a pioneering firm helping organisations integrate human, social, and natural capital into their decision-making. As Valuing Impact celebrates its 10th anniversary in 2025, I had the chance to sit down with Samuel for an unfiltered conversation about what’s broken in today’s sustainability landscape — and how we fix it.

Interview: Samuel Vionnet in conversation with Sarah Perreard
Sarah: Samuel, let’s start with your “why.” What’s the environmental or social challenge that drives you the most?
Samuel: Honestly? I care about all of them. I’ve worked on water stewardship, climate strategies, risk management, economic valuation — but if I had to choose a core theme, it’s how we account for value. Financial accounting completely ignores most of what actually matters for society and the environment. Fixing that system would transform how decisions are made — and that’s what drives me.
Sarah: How does that connect to global crises like climate change and inequality?
Samuel: We can’t manage what we don’t measure. Impact accounting is about putting real societal and environmental value into the same space as financial value — so leaders can make smarter decisions. Want to pick the right climate project? You need to know its social and environmental co-benefits, not just its carbon footprint.
Sarah: What keeps you motivated when the challenges feel overwhelming?
Samuel: Delivering those “aha moments” to clients — when data actually shifts their mindset. That’s what keeps me going. Plus, constantly challenging the status quo? That’s just fun.
Sarah: What’s one misconception about your work that you wish more people understood?
Samuel: That sustainability isn’t a checklist. Too many companies work in silos — climate here, biodiversity there, social equity over there. That’s nonsense. Everything is connected. Some of the so-called “positive impact” projects we’ve assessed actually had a net negative impact because they ignored those interconnections.
Sarah: You’re a big advocate for impact accounting. What’s the one trend businesses can’t afford to ignore right now?
Samuel: Measure what you actually want to manage. That means going beyond carbon and embracing holistic impact valuation — comparing social and environmental impacts alongside financial ones.
Sarah: Any tech innovations you’re excited about?
Samuel: Honestly, the biggest innovation is the concept of impact accounting itself. Financial accounting is part of what got us into this mess. The moment we measure societal value with the same rigor as financial value, everything changes.
Sarah: How do you see Earth Action’s role in this shift?
Samuel: EA is a front-runner. You’re creating the methods, data, and processes that will become the backbone of future impact accounting. This work matters — a lot.
Sarah: What’s the biggest missed opportunity you see in sustainability right now?
Samuel: Wasting money on useless projects. There’s so much fluff — projects that sound good but deliver little real value. Impact accounting helps cut through the noise and focus investments where they actually matter.
Sarah: You’ve worked across continents. How do you see consumer pressure playing into all this?
Samuel: In Europe, maybe. But globally? Not so much. Most people are too busy surviving to demand sustainability. The bigger levers are regulation, investor pressure, and geopolitics.
Sarah: What’s one piece of advice you’d give to CEOs trying to embed sustainability into strategy?
Samuel: Start with double materiality. Figure out where your biggest impacts and risks are — financially and socially. Then act on the data, not just gut feelings.
Sarah: And for the next generation of impact leaders — what’s your message to them?
Samuel: Know your values. Build partnerships. And remember: financial and societal value aren’t enemies. The future belongs to businesses that align both.
Sarah: Final words for world leaders?
Samuel: (Laughs) Yeah — if I could say it the way I really want to, I’d probably tell them to stop f*cking around and grow some… well, you know. But let’s just say: it’s time for real courage with a capital C. Work for the people, not just corporations, if you want to leave a legacy worth remembering.
Closing reflections
At Earth Action, we value exactly this kind of honesty and systems thinking. Samuel’s expertise doesn’t just inform our work — it challenges us to be sharper, braver, and more ambitious. As we continue to collaborate with experts like Samuel, we hope to accelerate the shift toward impact accounting as a mainstream business practice — because when we truly value what matters, business can become a force for regeneration.
This is also why we’re excited to announce that in 2025, the Plastic Footprint Network (PFN) — an initiative convened by Earth Action — will be teaming up with Valuing Impact and Samuel to take our work on plastic pollution even further. Building on the recently published PFN module that translates plastic footprint inventories into impacts on human health and ecosystem health, this next phase of the partnership will go a step further: translating these impacts into monetary value. This will allow companies to fully integrate the cost of plastic pollution into their decision-making and sustainability reporting — turning data into actionable insight.
Want to dive deeper into Samuel’s thinking? Check out his book:
👉 Impact Thinking: Apply critical thinking to sustainability decisions