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Dr. Reerink has more than 25 years of experience in promoting gender equality and social inclusion in international development, with a strong focus on the Asia-Pacific region.

Laura Blake has more than 20 years of experience in leading scientific programs and research in the environmental science and policy domain. She has deep expertise in surface water quality restoration and protection and has spent her career designing and implementing scientific studies to support efforts to protect human health and aquatic environments. She has significant knowledge of Clean Water Act rules and regulations and has extensive experience supporting federal and state regulatory programs with implementation of and compliance with the federal Clean Water Act.

Jessen Carroll is a human resources (HR) professional with more than 20 years of experience overseeing all aspects of HR, organizational communications, governance, and administration functions. She has experience leading organizational integrations and change management efforts. She also has operations management, business analysis, business process improvement, and project management experience. She can balance tactical day-to-day operational needs with a strategic grasp of long-term business objectives. 

Douglas W. Elmendorf, Ph.D., is Lucius N. Littauer Professor of Public Policy at Harvard University’s John F. Kennedy School of Government. He served as Dean of the Kennedy School from 2016 to 2024 and was previously Director of the Congressional Budget Office from 2009 to 2015.Elmendorf has held senior economic positions with the Federal Reserve Board, the President’s Council of Economic Advisers, and the Treasury Department, where he was Deputy Assistant Secretary for Economic Policy. He is a widely respected economist who has deep knowledge of many of Abt’s core research areas, including health care policy and approaches to increasing economic security.Elmendorf is the author of more than 30 publications and has testified before Congress on economic issues 50 times since 2005. 

Brian Chirwa is an agricultural and environmental scientist with over three decades worth of experience working on projects funded by the World Bank, the U.S. President’s Malaria Initiative (PMI), the Environmental Council of Zambia, and the Southern African Development Community (SADC). He brings 18 years’ experience on PMI-funded projects focused on indoor residual spraying (IRS) and insecticide-treated nets (ITNs) and has provided technical leadership, assistance, and high-level management for country-wide Zambian IRS and ITN campaigns. Brian also has three decades' worth of experience designing environmental information systems (EIS) for public organizations.

Lauren Pittenger comes to Abt with more than 20 years of experience working in or as a consultant to federal government agencies. She has strong grounding in research and research-based consulting to government clients. She also has extensive experience leading and growing business, managing technical and scientific projects, and coaching and supporting account teams. She has served as a director at Guidehouse, scientific program manager at Booz Allen Hamilton, and lab manager at the U.S. Department of Agriculture. She has worked with the Centers for Disease Control and Prevention (CDC), Food and Drug Administration (FDA), the Canadian Public Health Laboratory Network, the Gates Foundation and the Association of Public Health Laboratories.

Catherine Hersey, a senior associate, is a seasoned health services researcher and project manager with over 15 years of experience in both Medicare and Medicaid. Her research areas include the implementation and evaluation of accountable care organizations and other alternative payment models, maternal health, substance use disorder, meaningful use of electronic health records, and hospital-acquired infections. Hersey also has experience in quality measurement and improvement. In addition, she has experience in both quantitative and qualitative analyses and managing large and complex projects.

In his career as a senior finance and operations executive, Rehberger most recently served as the Senior Vice President, Chief Financial Officer of Engility, a Virginia-based government contractor.  He held similar positions with TASC from 2010 until its merger with Engility in 2015.  Rehberger helped guide both companies as the government industry cycled through a severe downturn and recovery, counseling the Board of Directors regarding strategy, enterprise risk management, cyber security, and compensation.  He previously held executive positions with telecommunications firms XO Communications and MCI. In 2017, Virginia Business awarded Rehberger the Virginia CFO of the Year award for his outstanding commitment to financial stewardship and dedication to the success of Engility.

Dr. Jonathan Dorn has more than 20 years of experience in the environment and energy space. He specializesin air pollutant emissions inventory development, air quality, data visualization, regulatory program support, energy systems, and air pollutant mitigation strategies.

William Tuleu leads strategic growth initiatives across the company's U.S. foreign assistance and domestic portfolios.