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Arla Lach




Executive summary


Arla has nearly 25 years of experience driving growth and leading effective teams at Grant Thornton. In her role as market managing partner, she helps nearly 1,000 audit and assurance, tax and advisory professionals provide personalized, high-quality services that go far beyond what clients might expect from a professional services firm.


She has spent her entire career at Grant Thornton, serving in a succession of high-profile leadership roles and, in turn, driving growth in Chicago, throughout the Midwest and across the firm. During her time as the firm’s Midwest Geography leader, she oversaw audit work for all clients served by Grant Thornton’s teams in Chicago, Minneapolis and Wisconsin. Her success in this role helped the firm achieve record revenues in both 2022 and 2023, and Arla herself was named a “Notable Gen X Leader in Accounting” by Crain’s Chicago Business.


Arla has also served as the chief of staff to the CEO and as an audit partner serving clients in industries as diverse as manufacturing, distribution, technology and professional services. The latter role helped her sharpen her skills for complex SEC filings as well as the implementation and maintenance of internal control systems.


Lastly, she is highly skilled in the development, execution and communication of firm strategy, contingency planning, budgeting, senior management transition and many other areas that are crucial to the day-to-day operations and long-term planning of the firm.




Professional qualifications and memberships


  • Arla is a member of the American Institute of Certified Public Accountants (AICPA), the Illinois CPA Society and the National Association of Corporate Directors (NACD).
  • In 2011, Arla was honored by the Illinois CPA Society, receiving the “Women to Watch” award in the emerging leader category.
  • In 2022, she was named a “Notable Gen X Leader in Accounting” by Crain’s Chicago Business.
  • Question for the web team: Can we add a separate section (with its own header) for “Awards”? 



Community involvement


  • Arla previously served as the audit committee chair and as a member of the Board of Directors for the Gateway Foundation. She also served on the board of the Step Up Women’s Network. Prior to that, she was the treasurer for Theatre Building Chicago.





  • Arla earned a bachelor’s degree in accounting from the University of Illinois Urbana-Champaign.

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