Stephen Callahan is a seasoned expert in transformation, risk management, and governance, with over two decades of experience advising multinational corporations and governments worldwide. His career highlights include leading tax function transformations, delivering sustainable performance improvements, and developing comprehensive tax strategies for major global industries, including Energy, Finance, and Government. Stephen has also been instrumental in coaching CFOs, Boards, and Audit Committees on international tax risk management and governance standards, ensuring compliance and enhancing overall organisational efficiency.

Throughout his career, Stephen has pioneered innovative solutions, such as a digital platform for benchmarking back-office performance and has played a critical role in shaping policy and regulation in multiple jurisdictions. His extensive international experience spans Europe, Asia, the Middle East, and beyond, where he has successfully led complex projects, including advising on significant geopolitical transitions and regulatory changes.