Grant Thornton appoints advisory services and industry practice leaders
Grant Thornton US has appointed Tom Puthiyamadam as head of advisory services and Martin Shanahan as head of industry.
Based in New York, Puthiyamadam joins Grant Thornton after nearly 28 years with PwC. He most recently served as transformation consulting leader, leading digital-powered transformation projects across large enterprises.
Before that, Puthiyamadam served as consumer markets consulting leader and global & US digital consulting leader.
He has a bachelor’s degree in finance from Binghamton University.
“Tom’s experience, knowledge of the market, and forward-thinking vision make him the ideal leader to steer our Advisory Services practice in this time of transformation for our firm and our clients,” said Jim Peko, CEO of Grant Thornton Advisors LLC.
Puthiyamadam joins Grant Thornton at a time of significant change. New Mountain Capital in May 2024 completed its acquisition of the mid-market accountancy, splitting it into an alternative practice structure with separate attest and non-attest businesses.
In January 2025, New Mountain acquired and merged Grant Thornton Ireland – a 2,800-person firm – with Grant Thornton US. The combined enterprise has 12,000 people across the US, Ireland, and other territories and has $2.7 billion in annual revenues.
The addition of the Ireland member firm to Grant Thornton US is likely driven by tax minimization strategies.
Ireland is a well-known tax haven. Accenture, despite being an historically American company, moved its corporate headquarters from Bermuda to Dublin 2009.
Based in San Francisco and Dublin, Shanahan will oversee operations, strategy, and growth initiatives for Grant Thornton Advisor LLC’s multinational industry practice.
Shanahan previously spent two years at Grant Thornton Ireland, where he was head of industry.
He has over 25 years of private and public sector experience in strategic planning, policy development, marketing, and investment decision-making. Shanahan has worked at the forefront of if Irish labor market policy, innovation, and development of enterprise.
He previously spent eight years as CEO of industrial development agency IDA Ireland. Before that, Shanahan was CEO of Forfas, the Irish government’s policy advisory board for enterprise, trade, science, technology, and innovation.
Shanahan has a higher diploma and master’s degree from the Technological University of Dublin, a master’s degree from Lancaster University in the UK, and a bachelor’s degree from Trinity College, Dublin.
“Today’s business climate is impacting all industries in a way that requires leaders to be forward-thinking and agile,” said Alasdair Trotter, chief revenue officer of Grant Thornton Advisors LLC. “Martin’s years of industry know-how and global perspective make him uniquely suited to help our Industry practice deliver high-quality solutions to our clients, while navigating the shifting landscape and historic new challenges that lie ahead.”
