Helping philanthropists, families, not for profits, advisors and businesses
to make a more meaningful impact.
How Boon can help
Philanthropy strategy
From conception and planning through to understanding what impact means to you and setting impact measurements and milestones, including helping to select and set up the right charity parter, and helping you figure out the right way to give, whether that's a DAF, a foundation or anything in between.
Partnerships and connections
Working with my extensive network of experts, philanthropists, not for profits and charitable organisations, I help you make the connections that matter so that your philanthropy can have the biggest impact.
Supporting companies and not for profits
Working with corporates on their sustainability and CSR strategies as well as with not for profit organisations to help define and deliver their high value fundraising strategy.
Supporting individuals, families & foundations
Wherever you are in your philanthropy journey, I can help you decide what type of philanthropy will best align with your business, wealth or succession goals whilst having the greatest impact - and being the most enjoyable.
Supporting Advisors and private client teams
I help wealth managers, private client advisors and family offices have confident, meaningful philanthropy conversations with clients. Through toolkits, training and custom workshops, I give advisors the tools to guide clients through their philanthropic journey.
Who is behind Boon?
Sianne Haldane is an independent philanthropy and impact consultant who helps families, philanthropists, businesses and not for profits design and deliver thoughtful, high-impact giving.
She brings over 20 years’ experience across philanthropy, charity, law, sustainability and social impact. Her work combines strategic clarity with practical delivery, helping clients move from good intentions to giving that is well structured, personal and genuinely useful.
Before founding Boon, Sianne was a lawyer at Linklaters working on human rights initiatives, Head of Planned Giving and Philanthropy at Cancer Research UK and Chief Impact Officer at Maanch, a social impact consultancy.
She has worked across charity, corporate sustainability and legal roles in the UK and South Africa. She has advised families, foundations, companies and private client teams on giving strategies, partnerships and impact.
Case studies
Building a charity from the ground up — Percent for Good
Mark, a former fund manager, wanted to reinvent how people give. His vision was a structure built around thematic giving portfolios — in effect, the equivalent of an "ETF fund", but for philanthropy. Working from discovery and research through innovation, planning and execution, Sianne helped turn that vision into reality. Percent for Good is now a fully operational charity.
Turning vision into impact — football as a force for change
Mr P, a successful entrepreneur, had always given in an unstructured way and wanted to uplift a specific community in South Africa — using football as the vehicle and leveraging high-profile partnerships to build a pipeline of professional talent. Sianne led the research, impact analysis and partner research, drove community engagement, and coordinated the professional service providers needed to create the legal entities and brand.
Bringing a family together around giving
A family had been giving in an unstructured way and wanted to create unity and a shared sense of purpose. Sianne facilitated a family discussion around the causes each member cared about and the impact they hoped to achieve. From there, she helped them develop a clear structure, align on the themes closest to them, and put their giving into practice — turning scattered generosity into a shared family mission.
Supporting a family office on rare disease
Working with a family office focused on rare disease, Sianne led the selection and due diligence of charity partners, managed the partnership, and supported the full grantmaking process — including ongoing evaluation to ensure the giving delivered real, measurable impact.
Guiding high-net-worth giving alongside trusted advisors
For Mr & Mrs L, Sianne carried out the research and due diligence and supported the shortlisting of beneficiaries, liaising with CAF and the family's wealth manager to ensure complete clarity on the objectives for their trust.
To help wealth advisors embed Legacy giving naturally into wealth and estate planning conversations with clients, Boon created resources for Private Client advisors including an advisory committee, case studies, a good practice guide and The Legacy Academy series of CPD resources.
Affiliations and networks
Sianne is connected to a number of philanthropy, private wealth and impact networks.
Former Chair of the STEP Global Philanthropy Advisors Group, STEP member
Affiliate trainer for Philanthropy Impact.
A keynote speaker at philanthropy and private advisor conferences.
Advisory Committee Member for UBP's Biodiversity Restoration Impact Fund and UBP Family Office affiliate partner for Client Philanthropy Advice
Former member of the Advisory Committee of the UN Global Compact UK.
Former Trustee of The Royal Commonwealth Society.
Former Trustee of Save the Rhino International.
Former Trustee of Mosaik Education
Testimonials
"Sianne helped me identify the strategy and objectives of my philanthropy. She ensured I had the right amount of engagement with the organisation, so I could understand how best to align with their priorities. As an entrepreneur and a scientist Sianne knew what would make me tick and found ways that I could engage with the organisation beyond financial support and evolved my journey so that I could mentor and join advisory boards."
Alison Howe, Philanthropist
Some organisations my work has impacted on
+44 (0)7947207291