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NSF OIG Organization Chart

Leadership Biographies

Allison C. Lerner assumed duties as Inspector General of the National Science Foundation in April 2009, reporting to the National Science Board and the Congress. As head of the Office of Inspector General, she recommends policies for promoting economy, efficiency and effectiveness of NSF programs and operations. She leads efforts to prevent and detect fraud, waste, and abuse; improve the integrity of NSF programs and operations; and investigate allegations of misconduct in science. She has chaired the Council of the Inspectors General on Integrity and Efficiency since January 2021 and served as its vice chair from January 2015 through December 2020.

In September 2016, Mark Bell was appointed Assistant Inspector General for Audits at the National Science Foundation OIG. Prior to his arrival at NSF, Mr. Bell served nine years with DHS OIG. At DHS OIG, Mr. Bell had several roles in the Office of Audits, including Chief of Operations, Deputy Assistant Inspector General, and Assistant Inspector General. Prior to his arrival at DHS OIG, Mr. Bell worked at the Department of Interior OIG in the Central Region Office in Denver as a program analyst, and then as the Chief of Staff for Audits. From 1992 to 2001, Mr. Bell was self-employed in the financial services industry and worked as a consultant to Bearing Point. He began his career in the U.S. Army, serving more than 11 years, including 8 years overseas, as a tactical communications officer with the 93rd Signal Brigade in Desert Shield/Desert Storm. Mr. Bell graduated from the University of New Hampshire with a bachelor’s degree in business administration and he earned a master’s degree in management from Webster University.

Mr. Chason joined NSF OIG as Counsel to the Inspector General in 2006. Prior to this, he held positions as an attorney with the United States Department of Justice and with the Government Accountability Office. Earlier in his career, Mr. Chason served for several years in the United States Army JAG Corps. He is a member of the State Bar of Georgia and the District of Columbia Bar.

As Deputy IG and Counsel, Mr. Chason leads the OIG Immediate Office, which serves the Office of Inspector General on a wide variety of matters. Legal Counsel provides comprehensive legal advice, counsel, and critical analysis to the IG and all OIG divisions; administers financial disclosure requirements for OIG staff; performs functions related to the Freedom of Information and Privacy Acts; and represents the office in external forums.

Megan E. Wallace has more than 27 years of experience as a federal law enforcement agent, of which more than 15 years have been in the IG community. Ms. Wallace joined the National Science Foundation Office of Inspector General as the Special Agent in Charge in 2014 and became the Assistant Inspector General for Investigations in 2018. As head of the Office of Investigations, Ms. Wallace is responsible for a wide spectrum of investigations, including civil, criminal, and research misconduct matters, involving organizations or individuals that receive awards from, conduct business with, or work for NSF. 

Ms. Wallace earned her Bachelor of Arts Degree from the University of San Diego in 1992 with a degree in Education and Spanish. She earned her Masters Degree in Policy Management from Georgetown University in 2011. Ms. Wallace is also a certified fraud examiner and earned a certificate in Key Executive OIG Leadership from American University in 2009.

Since November 2019, Karen Gambarani has served as Acting Assistant Inspector General for the Office of Management and Chief Information Officer at the National Science Foundation OIG. Previously, Ms. Gambarani served as Deputy Assistant Inspector General for Management and Chief, Investigative Support. Before her arrival at NSF OIG in 2011, Ms. Gambarani worked in the Prince William County Public School system. She began her career as an industrial engineer at Armstrong World Industries in Lancaster, PA, and The Richards Corporation in McLean, VA, and subsequently worked as a software engineer at Government Technology Services Inc. in Chantilly, VA. Ms. Gambarani received a Bachelor of Science degree in Industrial Engineering from Lehigh University and a Master of Science degree in Information Systems from George Mason University.

As head of the Office of Management, Ms. Gambarani provides policy, guidance, and customer support in the following areas:

  • Budget Planning and Execution (budget formulation and execution)
  • Financial Transaction Processing
  • IT Operations
  • Human Capital (personnel actions)
  • Travel and Training
  • Procurement-related matters
  • Operations Support (office space, furniture, lighting, and continuity of operations)
  • Policy and Planning (maintains and oversees revision of all OIG policies and strategic/annual planning)

Lisa Vonder Haar is NSF OIG’s chief of staff. She started her federal career in 2002 at the Department of Interior OIG and joined NSF in 2018. She serves as the IG's primary officer for legislative and press matters, and provides other senior-level support to the Inspector General. She can be reached at oigpublicaffairs@nsf.gov or 703-292-2989.