Thomas Widmer

Etienne von Streng is a co-founder of Streng SA, a tax law firm based in Geneva, Switzerland. Etienne received his law degree from the University of Lausanne (Switzerland), was admitted to the Zurich bar, and holds a Certified Tax Expert diploma. Etienne advises on Swiss and international tax matters for companies including listed and private multinationals, high net worth individuals, entrepreneurs, and families. His expertise includes in general tax optimization, frequent negotiations with ...

Fouad Sayegh is a partner in the tax team. His expertise covers most aspects of domestic and international taxation. He regularly advises high net worth families in their relocation, wealth reorganization, asset protection, estate planning and charitable projects, which often includes tax advice in relation to trusts, private foundations and investment vehicles. In the field of corporate tax, his practice includes advising on M&A transactions, corporate reorganizations, double tax treaty ...

Adriano Antonietti advises domestic and foreign banking and financial institutions, as well as collective investment schemes and asset managers on a wide range of matters, in particular regulatory issues, private placements, the drafting of banking contracts and certain tax related matters (FATCA, CRS). He also defends banks and their clients in a number of disputes and deals with all aspects of corporate and commercial law. His main fields include financial products and services, including r...

Partner Pierre Ducret is a partner and co-head of the Private Clients and Sports Law departments of CMS von Erlach Partners. He advises and assists clients in complex litigation, mainly in civil and commercial matters, usually with international ramifications. He is particularly active in the field of inheritance law. He also acts as counsel or arbitrator in international arbitration proceedings. In addition to his dispute resolution practice, Pierre Ducret advises his clients on wealth and e...

Carl Heggli is a top attorney recognized by Best Lawyers in the practice area(s) of Trusts and Estates and Wealth Management Practice. Carl, who practices law in Geneva, Switzerland, has been recognized since 2014. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Carl is held by other top lawyers in the same geographic and legal practice area.

Andrio Orler is a top attorney recognized by Best Lawyers in the practice area(s) of Tax Law. Andrio, who practices law in Geneva, Switzerland, has been recognized since 2026. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Andrio is held by other top lawyers in the same geographic and legal practice area.

Jamar E. Brown joins the Dispute Resolution and Private Clients groups in the Geneva office. In the dispute resolution field, Jamar represents international organisations in employment disputes before specialised administrative tribunals, including the Administrative Tribunal of the International Labour Organization. He is also a trusted advisor on internal investigations, disciplinary matters, and appeals before internal review bodies. In his private client work, Jamar specialises in regulat...

Nicolas Béguin is a top attorney recognized by Best Lawyers in the practice area(s) of Banking and Finance Law. Nicolas, who practices law in Geneva, Switzerland, has been recognized since 2025. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Nicolas is held by other top lawyers in the same geographic and legal practice area.

Sarah Busca Bonvin is a lawyer and tax expert specialised in both corporate and individual tax law. Together with M. Andrio Orler, she is responsible for CMS’ tax department in Geneva, which she joined in 2017. She worked for 15 years in the Geneva tax administration as Director of the tax affairs where she was responsible for tax rulings before being appointed Deputy Director-General in 2010. This experience has given her significant breadth and depth of knowledge and practice in many ...

Jacques Bonvin is a top attorney recognized by Best Lawyers in the practice area(s) of Corporate Governance and Compliance Practice, Corporate Law, Mergers and Acquisitions Law, Private Equity Law and Venture Capital Law. Jacques, who practices law in Geneva, Switzerland, has been recognized since 2019. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Jacques is held by other top lawyers in the same geographic and legal practice area.