About us

One Stone Advisors is a dynamic, purpose-driven, women-owned sustainability advisory firm

Our global team has been shaping sustainability leadership and impactful client outcomes for over 30 years.

As early pioneers of corporate sustainability in Europe, we co-developed the Triple Bottom Line with John Elkington (People, Planet, Profit).

Now our core focus is helping organisations embed that thinking and align with the UN 2030 Agenda. And we believe the push for a fairer, more regenerative future starts with us.

Our Impact

Our Vision

A world where sustainability leadership is mainstream.

Our Mission

To help clients become more effective sustainability leaders.

Our Values

Act with Integrity

We build trusted and respectful relationships

Make a difference

We aim beyond compliance for positive impact

Empower for good

We share knowledge and networks with a focus on the future

We’re proud to be a B Corp

Sustainability is what we do—and core to who we are. We’ve been a certified B Corp in AANZ since 2019, with verified high standards of performance, transparency, accountability and continuous improvement.

In 2022 we successfully recertified with a B Impact Score of 134.7 points—among the highest in our sector and region and more than double the median score for most businesses.

B like us

We believe in the power of business to drive women’s economic empowerment, diversity and inclusion

We are a certified women-owned business with WEConnect International. By choosing us, you are uplifting women in business and demonstrating genuine commitment to a small, diverse and inclusive supplier.

We actively go beyond reducing adverse social, environmental and economic impacts to create net positive value

We are committed to Justice, Equity, Diversity and Inclusion principles and reducing our environmental impacts by procuring responsibly and delivering on our climate action plan.

We are proud to support these initiatives:

We’re a passionate, dynamic, global team

Our pioneering women-led team has over 30 years at the leading edge of responsible business practice—across government, blue-chip multinationals and small business.
We bring the perfect balance of global expertise and local experience to empower effective sustainability leadership. We get the big picture, we also get the detail—and we care about quality outcomes.

As strategy, impact and engagement specialists, we work across a wide range of ESG topics and industries—including government, business, not-for-profit, arts, culture & tourism, finance, consumer goods, health & social services, infrastructure and transport.

Hover on our profiles to know more.

Andrea Spencer-Cooke
CEO & Sole Director

With 30 years at the leading edge of corporate sustainability, Andrea is an expert at strategic integration of ESG and the SDGs for measurable positive impact. One of Australia’s first trained B Consultants, a B Council member and Banksia judge, she brings a wealth of global best practice and stakeholder insight to your leadership journey.

Alexandra Stafferton
Associate

Alexandra helps leaders in energy, finance and tech embed the latest B Corp standards into how their business runs. She helps businesses to unlock growth, reduce ESG risk, and attract values-aligned capital.

As co-lead of B Local Sydney, a 200+ business-strong network, Alexandra can help connect you directly into the 10K+ global B Corp community and help you build visibility, credibility, and momentum from day one.

Jennifer Moses
Senior Consultant

Jennifer is passionate about embedding sustainability in the arts, culture and creative sectors and ensuring organisations are ESG-ready. She has experience in commercial strategy, scaling business and building cultural precincts and holds degrees in commerce, sustainability and social impact.

Fran Van Dijk
Advisor

Fran’s forte is helping emerging sustainability leaders focus on what matters most. At C-suite level, she asks the right questions, guides priority-setting and helps turn climate ambition to reality. Fran is a former Board Member of the Scottish Environment Protection Agency and B Corp Ambassador.

Jacqueline Mees-Buss
Associate

If you’re looking to embed responsible business, see Jacqueline. Her core strength is guiding large organisations through the transformation process to become better corporate citizens. Formerly with Unilever, Jacqueline is also a lecturer and researcher at the University of NSW.

Sahera Sumar
Associate

Sahera is our global women in leadership consultant. An advocate for inclusion, diversity and human rights, she works to amplify and empower women’s contribution and strengthen diversity pipelines with particular focus on emerging markets.

Barbara Albert
Associate

Barbara is our carbon guru. A registered Climate Active consultant and Co-CEO of 100% Renewables, she specialises in helping large energy users develop net zero strategies and achieve carbon neutrality.

Amy Brown
Associate

For award-winning sustainability writing and reporting, Amy is the person to talk to. She has 17 world class reports in her portfolio, along with high-level policy papers on human rights and the SDGs, ethics training modules, modern slavery statements and more.

Kay Formanek
Associate

Kay is passionate about helping organisations unleash the power of Diversity & Inclusion. As well as an author, executive coach and consultant, she is visiting lecturer at leading business schools and Founder and CEO of Diversity and Performance BV, based in the Netherlands