Executive Team Biographies


Thomas M. Connelly, Jr., Ph.D.
Chief Executive Officer

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    Thomas M. Connelly, Jr. is the CEO of the American Chemical Society. Prior to joining ACS, he served as Chief Science and Technology Officer, and then as Chief Innovation Officer for the DuPont Company. In these roles, he was responsible for science and technology, with special emphases on polymer science, chemical process development, and later, bioprocessing for chemical synthesis and production. At DuPont, Dr. Connelly led R&D organizations and businesses, while based in the US, Europe and Asia.

    Dr. Connelly graduated with highest honors from Princeton University with degrees in Chemical Engineering and Economics. As a Winston Churchill Scholar, he received his doctorate in chemical engineering from the University of Cambridge. In 2016, Dr. Connelly was elected to the National Academy of Engineering. He has served in advisory roles to the U.S. Government and the Republic of Singapore.


LaTrease E. Garrison
Executive Vice President, ACS Membership
and ACS Education

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    LaTrease E. Garrison received her BS in chemistry from Howard University and completed her MBA degree at Strayer University where her research focused on succession planning for the non-profit organization. She received her certificate in diversity and inclusion from Cornell University. She joined ACS in 1992 as a Program Assistant for Chemical & Engineering News magazine. In 1996 she moved to the Education Division where she held several positions including Senior Program Manager of Undergraduate Programs. In 2005 Ms. Garrison was appointed to the position of Special Assistant to the Director of the Education Division. She previously served as the Assistant Director of the Member Communities/ Department of Volunteer Support and Director of the Administrative and Programmatic Technology group and the Professional Advancement Team. She has also served as staff liaison to various ACS Committees and Task Forces and is a trained facilitator for courses within the ACS Leadership Development System.


Manuel Guzman
President, CAS

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    Manuel Guzman received a BS and an MBA in finance from Seton Hall University. Before being named President of CAS, Mr. Guzman was the Executive Vice President of Learning, Research Solutions & International for Cengage Learning, responsible for a $2B product development operation including strategy, content, development and product/platform technology along with leading the company's international operations. He has held various executive positions within the information industry including President of Thomson Learning, Career & Professional Group.


Al Horvath
Treasurer & Chief Financial Officer

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    Al Horvath is the Treasurer and Chief Financial Officer of the American Chemical Society, effective Feb. 11, 2019. Prior to joining ACS he served as Chief Operating Officer and Under Secretary for Finance and Administration at the Smithsonian Institution. In that role, he was responsible for financial, business and administrative activities of the largest museum, research and educational complex in the world. Prior to joining the Smithsonian, Mr. Horvath spent more than two decades working in administration for some of the leading research universities in the country including Penn State, Columbia University, California Institute of Technology, New York University, and Carnegie Mellon University. He began his career at Mellon Bank in his hometown of Pittsburgh before moving into higher education. A native of Pennsylvania, Mr. Horvath earned his master's degree in business administration at Duquesne University and his bachelor's degree in accounting at Penn State.


Mary Kirchhoff, Ph.D.
Executive Vice President, Scientific Advancement

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    Mary Kirchhoff received BS and MS degrees in chemistry from Russell Sage College and Duquesne University, respectively, and a Ph.D. in organic chemistry from the University of New Hampshire. Dr. Kirchhoff served for nine years on the faculty at Trinity College in Washington, D.C., and three years as an American Association for the Advancement of Science (AAAS) environmental fellow and visiting scientist at the U.S. Environmental Protection Agency. She spent three years with the ACS Green Chemistry Institute before moving to the ACS Education Division, where she served as Director from 2005-2016. Dr. Kirchhoff is a Fellow of AAAS and a member of the Chemical Sciences Roundtable.


Martha K. Lester
Vice President, Strategy Development

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    Martha Lester received her BA degree in chemistry from the University of Dayton, and an MS in Chemistry and Curriculum & Instruction from the University of Maryland. She joined ACS in 1987 and spent 10 years developing curriculum materials in the Education Division. In 1996, she moved to the Membership Division where she assisted with the design and implementation of the ACS Leadership Development System and the ACS Career Navigator. In 2015 Ms. Lester was appointed to her current position where she works with the Chief Executive Officer to assist the Board of Directors in developing, implementing, and monitoring a coherent strategic plan for the Society. She has served as staff liaison to Board, Council, and Joint-Board Council committees and is a certified facilitator for many of the courses within the ACS Leadership Development System.


Flint Lewis
Secretary & General Counsel
Director, Office of the Secretary and General Counsel

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    Flint Lewis has undergraduate and JD degrees from the University of San Diego. He worked as a litigation attorney in a San Diego law firm, then served for eight years as counsel and senior policy analyst for the US House of Representatives. Mr. Lewis served with the American Red Cross as a government relations officer and as chief of staff to ARC President Elizabeth Dole. In 1996, he became director of ACS' Office of Legislative and Government Affairs and assistant secretary. He was elected Secretary in 2002 and became General Counsel in 2004.

James Milne

James Milne, Ph.D.
President, ACS Publications

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    James Milne, Ph.D., is the President for ACS Publications. In this role he leads the strategic planning and overall management responsibility for the ACS' portfolio of 60 peer-reviewed journals, and the operations of Chemical & Engineering News. Dr. Milne has over 25 years of experience in scientific publishing and has held senior positions at Elsevier, the Royal Society of Chemistry, and at Wiley. With this breadth of experience across a range of organizations, he has been directly involved with most of the leading chemistry societies. Dr. Milne has offices in both Oxford, UK, and Washington, D.C., USA, reflecting both the global nature of scientific publishing, and the global role the ACS plays in this context.


Scott Oliphant
Executive Vice President, Human Resources

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    Scott Oliphant earned a BS from The Pennsylvania State University. Prior to joining ACS Human Resources in 2007, he worked for a number of multinational firms, including JDA Software, Motient Telecommunications, and Arthur Andersen Business Consulting. Mr. Oliphant's professional expertise includes compensation and benefits, diversity and recruitment, training and development, mergers and acquisitions, and legal compliance.


John Sullivan
Chief Information Officer, Washington IT Operations

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    John Sullivan received a BS degree in Information Technology Management from the University of Maryland, University College. Prior to joining ACS in 2005, he served as Chief Information Officer at AARP. Before AARP, Mr. Sullivan led the information technology departments at a number of other non-profit organizations, including the National Society of Professional Engineers and the Association of Trial Lawyers of America.