Roberts specializes in working with families with US connections and inbound/outbound investments to the country. He is qualified as a tax professional in the UK and also provides US/UK cross-border tax planning. The firm is aiming to grow its practice in the “critical area” of international taxation, said Joe Toce, the firm's office managing director in New York.

Roberts' previous career includes 10 years at Citi Private Bank, where he was responsible for the development and implementation of structures such as trusts and corporations to meet the tax-planning requirements of multi-jurisdictional clients. Before joining Citi Roberts was a member of Arthur Andersen's global private clients services team.

“The addition of Roberts addresses a growing segment of our high net worth client base looking for assistance in international tax planning," said Mark Vorsatz, chief executive of WTAS.

WTAS has offices in Baltimore, Boston, Chicago, Greenwich, Harrisburg, Los Angeles, New Jersey, New York City, Palo Alto, Philadelphia, San Francisco, Seattle, Washington, DC, and West Palm Beach.