Founder
Boon Impact
Sianne is an independent impact and philanthropy consultant, she helps to bring philanthropic vision into reality, helping Corporates, Families and Philanthropists achieve their impact goals. She is a dual qualified STEP lawyer with over twenty years experience working and consulting in the commercial and third sector with companies, individuals and not for profits.
Sianne was formerly Chief Impact Officer at Maanch, an Impact consulting firm where she worked with corporates to embed sustainability programmes. Before then, Sianne worked at Cancer Research UK, the largest charity in the UK, heading up philanthropy and strategic partnerships. She started her career as a lawyer in South Africa at Linklaters, embedding human rights into businesses. Sianne also has a Post Graduate diploma in Psychology with a focus on using coaching to deliver change.
Sianne is Chair of the STEP Global Philanthropy Advisors Special Interest Group. She sits on the Advisory Committee of the UN Global Compact UK, is a Judge on the Wealth for Good Awards and acts as an advisor on UBP's Biodiversity Restoration Impact Fund. Sianne sits on the board of the music production company Serious, and on the board of the Royal Commonwealth Society, Save the Rhino and Mosaik Education.
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