Oak Foundation

Esther Nørregård-Nielsen is the director of Oak Foundation Denmark, part of the international philanthropic organization Oak Foundation, which is headquartered in Geneva. Trained as a nurse, she holds a cand.scient.soc. and a Ph.D. in sociology, was previously a postdoc at the University of Copenhagen, and spent more than 11 years as owner and director of the analysis and consultancy firm Rådgivende Sociologer, working in evaluation, organizational development, and social analysis. She authored Pædagoger i skyggen and co-authored Klimaets sociale tilstand, serves as an external examiner in the social science and economics examiner corps, and participates in board work in the social sector.

Adriana Craciun is Senior Adviser and Head of Organisational Strengthening and Effectiveness at the Oak Foundation, where she leads an international philanthropic area of work focused on organisational development and grant-making practices. She has more than 25 years of experience in capacity development, including European and global initiatives supporting civil society organisations. She is an accredited executive coach.

Brian Robson is Director of Housing & Homelessness at Oak Foundation, a role he assumed in 2024, where he leads a London-based team of seven supporting organisations working on homelessness and housing in the UK and United States. He previously served as Executive Director (Policy & Public Affairs) at the Northern Housing Consortium, overseeing policy, communications, and member engagement, and earlier spent four years at the Joseph Rowntree Foundation. A Chartered Member of the Chartered Institute of Housing, he sits on the Institute's Policy Advisory Committee and has served as a local councillor in a London borough and as a school governor.

Geraldine Limborg is Director of Operations at Oak Foundation, where she oversees finance, HR, IT, administration, legal, and facilities across the organization's global operations. She has held roles in both the private and non-profit sectors and has experience working within multinational network organizations.

Mariam Kenza Ali is Head of Nature and People at the Oak Foundation, where she oversees global grantmaking portfolios focused on natural resource management and climate action. Her career spans environmental and climate philanthropy in the US and Europe, international NGOs, and multilateral processes, including prior work at the Packard Foundation, where she developed a $30 million transnational climate and forests strategy and co-created a community-based grassroots organising program. She previously led IUCN's World Heritage Outlook, an assessment of more than 250 natural World Heritage Sites, and her areas of focus include multilateral environmental agreements, protected area policy, biodiversity conservation, and renewable energy policy.

Nathan Argent is Director of Global Climate Initiatives at Oak Foundation, where he focuses on clean energy opportunities and partnerships across Europe, India, China, Sub-Saharan Africa, Southeast Asia, and Brazil. He has more than 25 years of experience in climate action and clean energy transitions. He is Emeritus Chair of the Funders Table, a network of 28 global climate foundations, and holds board and committee roles with the Tara Climate Fund and the Clean Air Fund.

Siobhain Coburn is Head of Finance at Oak Foundation and a Chartered Accountant. She has worked in the UK, Malawi, Kenya, South Africa, and Switzerland, across organizations at varying stages of development. Her experience includes financial management, resource allocation, and staff development.

Virginia Ruan is Head of Communications at Oak Foundation. Her areas of focus include communications strategy, external affairs, crisis communications, advocacy, depolarisation communications, and storytelling, as well as editing, writing, training, and mentoring.

Managing Director and Head of European Asset Management, based in London, managing the firm's European equity investments across asset classes. He previously worked in real estate audit at Ernst & Young.