Every significant transaction exposes the gap between advisors who understand the numbers and those who understand the decision. Most can produce a model. Fewer can pressure-test the assumptions behind it. And fewer still can walk into a room of seasoned investors — having sat on that side themselves — and speak with equal authority about both the process and the logic it serves.

When ownership changes hands, when capital is raised, when a founder chooses how to exit a business built over decades — the stakes are not merely financial. They are irreversible. The asymmetry between a well-advised transaction and a poorly-advised one is enormous, and it rarely announces itself in the term sheet. It appears in the gaps: the question no one thought to ask, the assumption no one challenged, the dynamic no one anticipated because no one in the room had been on the other side.

This is where most advisory relationships break down. Not from a lack of technical competence, but from a fundamental absence of perspective. A banker who has never deployed capital as a principal. An investor who has never run a competitive sale process. Neither alone can offer what a transaction of consequence requires.

Marine Charbonnier began at Deutsche Bank, where a career in investment banking means learning to structure the world before you have the luxury of an opinion about it. The discipline of IB is not romantic — it is relentless precision under pressure, the ability to hold enormous complexity in your hands while presenting it with clarity to people who will not forgive you for being wrong. Marine spent years doing exactly this: building the processes, managing the diligence, executing the transactions that move capital from one set of hands to another at scale.

Then came Carlyle, and a different kind of reckoning. As an investor in Carlyle's European Buyout fund, the work is no longer about executing a process someone else designed. It is about deciding — about being accountable, with real capital at risk, for whether a business will grow, whether a management team can deliver, whether the entry price is defensible. A hundred opportunities assessed before writing a cheque. The quality of that judgment is, ultimately, the only thing that matters.

What Marine brought back from that experience was not a credential but a fluency — an ability to read a situation through both lenses simultaneously. To see where a process might be optimised for optics rather than outcomes. To sense when an investor's objection is substantive versus tactical. To know, from having lived both, where the real decisions are made and who, in any given room, is truly driving them.

Sunstone Advisory was founded on this conviction: that the best transaction support does not come from technical mastery alone, but from understanding how investors actually think — not as a theory, but as a daily practice. The firm works with companies, founders, family businesses and investors in situations where ownership, leadership and capital intersect. Where the stakes are high enough that the choice of advisor is itself a consequential decision.

In practice, this takes three forms. For companies and founders navigating a sale or acquisition, Sunstone handles the full arc of M&A advisory — from process preparation and management, through due diligence oversight, valuation and structuring, to negotiation, documentation and closing. Not as a distant intermediary, but as a partner embedded in the team, acting as a direct counterpart to management throughout.

For businesses already within a portfolio — whether PE-backed or not — the work of portfolio support and exit preparation is equally demanding. Value creation takes time, and the path from ownership to exit is rarely straight. Sunstone works alongside management on the full scope: add-on acquisitions, investor and board interactions, financing and refinancing, equity story refinement, and the preparation of exit processes that are ready when the moment is right.

And for founders or management teams raising capital, fundraising advisory is where the dual perspective matters most acutely. It is one thing to build a compelling equity story. It is another to anticipate every question an investor will ask, to know which objections are genuine and which are posturing, to manage the dynamics of a competitive process with institutional counterparts who do this every day. Sunstone does not prepare you for investors. It represents you in front of them — having been one.

Across twenty-plus closed transactions — spanning large-cap flagship investments and mid-market acquisitions, disposals, add-ons, financings and fundraisings — and more than one hundred opportunities assessed, this is the experience that shapes every engagement. Not as a resume line, but as a practical reservoir of pattern recognition. The firm is independent, fully aligned with client objectives, and free of the conflicts that come with institutional affiliation: no proprietary products to push, no cross-selling agendas, no dilution through layers.