Tom is Managing Member and founder of Zaino Hall & Farrin LLC, a boutique law firm focusing on multistate tax controversy, planning, and policy. He serves as Chair of the Board of Directors for the Ohio Chamber of Commerce. He also serves as Immediate Past-Chair of The Ohio Society of CPAs and as a member of AICPA Council. Tom assists clients with business tax issues and represents many multistate and multinational companies and their owners and executives, before various state departments of revenue across the country, as well as before the Ohio Department of Taxation, other federal and state agencies, municipal tax authorities, the Ohio Board of Tax Appeals and the Ohio General Assembly.

Tom was the initial drafter Ohio's Commercial Activity Tax and the recent Ohio Municipal Income Tax reform law.

Tom served as Ohio Tax Commissioner and a member of the Governor Bob Taft’s cabinet from 1999 to 2003. As Tax Commissioner, he worked closely with tax administrators in other states as a participant in the Federation of Tax Administrators, the Multistate Tax Commission and as chair of Ohio's delegation to the Implementing States Committee of the Streamlined Sales Tax Project.

Prior to his role as Tax Commissioner, Tom was a tax partner at PricewaterhouseCoopers, LLP.