Arthur Armstrong is Debevoise’s Executive Director. He participates with other firm leaders in the development and implementation of strategic initiatives, and supports the firm’s Presiding Partner and Management Committee in governance processes. He oversees the firm’s administrative and paralegal support globally, and is responsible for the management of operations and expenses. Mr. Armstrong is a member of committees overseeing the firm’s legal talent development, development and advancement of women attorneys, space management, technology and pension plan investments.

Mr. Armstrong joined Debevoise in 2007 after spending 20 years at McKinsey & Company, first as a management consultant in its London and New York offices, then later as chief of staff in the development of its technology practice, and finally on special assignment to the firm’s Managing Director in a review of McKinsey’s administrative support globally. While at McKinsey, Mr. Armstrong co-authored Net Gain – a book published by the Harvard Business School Press on the topic of Web-based business models – as well as articles for the McKinsey Quarterly on similar topics and on corporate organizational structures. Mr. Armstrong obtained his B.A. (Hons) in Modern Languages from Oxford University and his MBA from the Wharton School at the University of Pennsylvania.


  • Wharton, M.B.A.
  • Oxford University, B.A.