The Anti-Greenwash Charter: From One Brief to a Shared Commitment.

How a simple client challenge became a growing, global movement for progressive sustainability communication

Sustainability is one of the most important conversations of our time, but also one of the hardest to get right. For years, organisations have struggled with how to talk about their environmental and social impact without overselling, oversimplifying, or retreating into silence out of fear of getting it wrong.

On one side is greenwashing, the exaggeration or distortion of progress. On the other is greenhushing, the choice to stay silent, even when meaningful work is happening.

It’s in this space, between overstatement and understatement, that The Anti-Greenwash Charter was born.

But it didn’t begin as a campaign or a grand industry initiative. It started with a single client brief.

A Real Client, a Real Problem

Back in 2021, a client of our agency partner, Gusto, was preparing for B Corp certification. They wanted their sustainability messaging to reflect the rigour of their internal efforts. They were looking for clarity and confidence, not just compliance.

At the same time, the UK’s Competition and Markets Authority had launched its Green Claims Code, putting brands on notice: misleading or vague environmental claims were no longer just bad practice, they were a legal risk.

That combination of pressure and principle led to a new idea.

“We were seeing the same tension everywhere,” says Charlie Martin, founder and CEO of The Anti-Greenwash Charter. “Organisations genuinely trying to do the right thing were afraid to speak up. Others, less careful, were making bold claims without the substance to back them. We needed a way through the noise.”

So the team asked: what if organisations published how they approach sustainability communications? Not just what they say, but how they decide what’s fair to say?

A Straightforward but Powerful Idea

The result was the first Green Claims Policy, a public statement setting out how an organisation manages its sustainability communications: how claims are checked, who’s involved, what standards are used, and where there’s still work to do.

It wasn’t flashy. But it was grounded. Honest. And incredibly useful.

“We weren’t giving people a script,” Charlie explains. “We were helping them show their working. That’s what builds trust, not the slogan, but the system behind it.”

For that first B Corp client, the policy became a cornerstone, internally and externally. It helped align teams, meet legal guidance, and communicate with confidence.

Soon, others followed.

From One Policy to a Charter

Word of the idea spread – first quietly, then more widely. More organisations wanted to develop Green Claims Policies. More teams wanted guidance. What had started as a single solution became a conversation. A community. And then, a shared commitment.

The Anti-Greenwash Charter was shaped by that energy. It’s now a growing alliance of organisations who want to raise the bar for sustainability communications -brands, agencies, campaigners and consultants committed to saying what they mean, and meaning what they say.

“It wasn’t a top-down initiative,” says Charlie. “It came from people in the work – marketers, sustainability leads, legal teams – who were all trying to do this better. We just gave it a name, and a framework.”

Why It Matters Now

The stakes are only getting higher. Public trust is fragile. Regulatory pressure is increasing. And the climate crisis is unfolding in real time.

In this context, the old playbook – smooth the edges, tell the best version of the story, avoid saying too much – doesn’t hold up.

But going quiet isn’t the answer either.

“Greenhushing is becoming as dangerous as greenwashing,” says Charlie. “If responsible organisations feel they can’t talk about their progress, we lose momentum. And that’s bad for everyone.”

The Charter offers a different path. One built on transparency, process, and shared responsibility. It doesn’t ask for perfection – it asks for accountability.

It helps organisations speak honestly, even when the story is still in progress.

What Comes Next

Since launching, The Anti-Greenwash Charter has helped a number of organisations publish Green Claims Policies, align teams, and rethink how sustainability is communicated. It continues to grow with input from legal experts, regulators, campaigners and the people doing the daily work of marketing and messaging.

“What makes this powerful is how practical it is,” says Charlie. “We’re not just pointing out the problems – we’re building tools to help fix them. And we’re doing it together.”

The Charter isn’t a badge. It’s a collective mindset. A commitment to open, accurate, and meaningful communication about sustainability.

It started with one client asking one honest question.

And it’s becoming a shared answer, shaped by those ready to lead with clarity and care.

Communicate About Sustainability with Confidence

If your organisation wants to protect its reputation, reduce greenwashing risk, and communicate sustainability with confidence, we’d love you to join us.

📢 Become a signatory of The Anti-Greenwash Charter.
Shape the future of responsible communication and show stakeholders what honest, trusted sustainability leadership looks like.

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