Eric Campbell ❤️
Director of Advising

Eric Campbell brings four years of experience designing and implementing social impact strategies and programs, with particular specialization in corporate philanthropy and impact investing.  In his previous role as a Senior Associate for Advisory Services at Arabella Advisors, Eric worked with a mix of foundations, corporations, donor collaboratives, and family and individual donors on deepening their impact. His work ranged from designing new philanthropic strategies to sourcing and evaluating potential impact investments and covered issues stretching from carbon credits to affordable housing.

Prior to his time at Arabella, Eric held roles in market research and public policy. He has a BA in Political Science from Colorado College. When he’s not designing for impact, Eric spends his time mountain biking, skiing, and attending concerts.

Heidi Sumser ❤️
Sustainability Associate

Heidi has over 15 years´ experience at the intersection of international development and climate finance, having worked in micro, small and medium-sized enterprise (MSME) banking, green finance and impact investing with mission-driven, private sector companies focused on emerging markets. She is a specialist in sustainability, small-business banking, and developing, managing, and growing new, strategic business initiatives. She is a skilled relationship manager and partnership developer with an extensive international network and the ability to engage stakeholders across sectors.  

Heidi worked as Green Lending Officer at responsAbility Investments, a Swiss leader in impact investing, managing a clean energy debt portfolio of financial institutions in Latin America for the Global Climate Partnership Fund (GCPF). Prior, she worked for the German ProCredit Holding based in Bolivia at Banco Los Andes ProCredit where she worked in the business and credit risk departments and then led the creation and implementation of sustainability, including green finance, as a new, strategic area. She also brings experience in development finance consulting and the non-profit sector.

Heidi is currently a mentor to sustainable start-ups at Bethesda Green´s Innovation Lab, a participant in a competitive global learning program for circular economy with the Ellen MacArthur Foundation and a guest lecturer on circular economy at universities in the United States and Peru. She earned a master´s degree in Development Economics and International Business Relations from the Fletcher School at Tufts University a bachelor´s degree in International Relations from Johns Hopkins University.

Sonya Knight ❤️
Director for Accounting

Sonya is an accountant with a deep love for numbers and a passion for growing businesses. She is the lead for Marsh Creek Social Works’ accounting practice and manages corporate real estate offices.

Sonya has worked throughout the accounting field, most recently as the Director of Finance and Operations for Knight & Company, and as a public accountant for several CPA and accounting firms. She has also worked in public and private accounting and performed audits to ensure compliance with state and federal regulations. Sonya obtained her bachelor’s in Accounting from Norfolk State University while working full-time for a global manufacturing plant. She later received her Masters in Business Administration from Virginia Wesleyan University. 

Dana Jones

Bookkeeping Specialist

Dana Jones is a financial professional with experience in budgeting, accounting, and fiscal management across government, nonprofit, and private-sector organizations. She currently serves as a Budget Analyst with the United States Air Force Academy’s Department of Physics and Meteorology, where she manages departmental and research center budgets exceeding $3 million, develops budget forecasts, oversees government purchase card programs, and ensures compliance with federal financial regulations. Throughout her career, Dana has earned a reputation for accuracy, efficiency, and strong organizational skills while supporting leadership with sound financial planning and reporting. 

Before joining the Air Force Academy, Dana served as a Bookkeeper for Lake City Community Church and as Finance Manager for Chosun Gift Shop, where she managed budgets, payroll, financial reporting, tax compliance, and inventory systems. She holds a Master of Science in Accounting from Michigan State University and graduated magna cum laude from Hope College with a bachelor’s degree in Business Administration and Spanish. Dana’s professional excellence has been recognized with the United States Air Force Academy’s Basic Sciences Division Civilian of the Quarter and Department of Physics and Meteorology Civilian of the Year awards in 2024.

Dr. Eric W. Miller 🇺🇸 ❤️
CEO & Founder

Eric founded Marsh Creek Social Works to pursue happiness for all, by connecting people, organizations, and purpose.  Eric is a strategic management expert with over two decades of strategy design, development, and implementation experience in both government and the social sector.

Prior to working with Arabella Advisors as an executive advisor to the CEO/COO, Eric served as the chief strategy architect for the Department of Defense’s efforts to receive US service member remains from North Korea, and as the lead strategic planner for the US intelligence community’s response to both BREXIT and the 2016 presidential nomination briefing process.   

Eric is a certified nonprofit consultant (CNC), and both presents and publishes social sector evidence-based research. Eric is currently serving as the board president for a Virginia-based nonprofit and as a communications advisor for a Canadian nonprofit focused on social economy research.  

Eric is also an adjunct professor at the George Mason University School of Business, teaching courses on global business economics.  Eric’s doctoral and post-doctoral studies examined scaling social impact within social enterprises and nonprofit organizations. In addition, Eric earned an MBA, a master’s in strategic intelligence, and a master’s in financial planning.

Katherine Lorenz ❤️
Senior Advisor for Philanthropy

Katherine Lorenz is President of the Cynthia and George Mitchell Foundation (www.cgmf.org), a grantmaking foundation focusing on environmental sustainability in Texas. She is the Leader of the Next Gen of the Giving Pledge, and Inside Philanthropy recently named Ms. Lorenz one of the most powerful heirs in philanthropy.

Previously, she served as Senior Advisor for the National Center for Family Philanthropy (www.ncfp.org) and Deputy Director for the Institute for Philanthropy (www.instituteforphilanthropy.org). Prior to that, Ms. Lorenz lived in Oaxaca, Mexico for six years where she co-founded Puente a la Salud Comunitaria (www.puentemexico.org), a non-profit organization working to advance food sovereignty in rural Oaxaca. She continues to be involved with Puente’s work as an active board member. Before founding Puente, she spent two summers living in rural villages in Latin America with the volunteer program Amigos de las Américas and later served on their Program Committee and as a trustee of the Foundation for Amigos de las Americas.

Additionally, she currently serves on the Boards of Directors of the Environmental Defense Fund (Vice-Chair), the Tinker Foundation, and the Endowment for Regional Sustainability Science, and formerly was a Fellow and later Board Chair at the National Center for Family Philanthropy, Board Chair of The Philanthropy Workshop, a Board Member of Exponent Philanthropy, Resource Generation, the Amaranth Institute, and a member of the National Academies’ Roundtable of Science and Technology for Sustainability. Ms. Lorenz serves on the Advisory Council of Boldly Go Philanthropy, the Leadership Council of the Greater Houston Community Foundation, and the National Advisory Committee of USC’s Irene Hirano Inouye Philanthropic Leadership Fund, and as a Senior Advisor for Philanthropy for Marsh Creek Social Works. Ms. Lorenz holds a B.A. in Economics and Spanish from Davidson College.

John Hamilton 🇺🇸 🦅
Senior Advisor for Military & Veterans Services

John has over four decades of leadership experience and expertise in policy and strategy development and implementation, and resource programming within the Department of Defense.

During his time in government service, he led numerous diverse teams and organizations focused on complex, strategic-level transformational issues, including the restructuring of major organizations, rebalancing strategic assets based on national-level policy and strategy shifts, and relocation of large organizations during the Congressionally directedBase Realignments. John also has over 20 years of experience living abroad and working with international partners on defense and humanitarian-related issues.

John has a Masters in Human Resource Management and a Masters in International Studies. He attended the Harvard Senior Fellowship Program in 2015.

Dr. Rozlyn Engel 🦅 ❤️
Senior Advisor for Global Economics

Roz is a Distinguished Professor of Practice at the U.S. Naval Academy, where she teaches courses on economics and foreign policy.

She has held several high-level positions in the U.S. government, including at the U.S. Treasury, the National Intelligence Council, and the U.S. Department of Defense. She grew up in Mountain Lakes, NJ, and raised her own family in Millburn.

Sarah Stremlau  ❤️
Senior Advisor for Nonprofits and Social Enterprises

Sarah Stremlau is the Chief Strategy Officer at Orr Group, a full-service philanthropic support firm, in which Sarah leads the development and implementation of a firmwide strategy to support the organization’s continued evolution, expansion, and maturation. In addition, Sarah oversees Orr Group’s strategy practice area, which helps nonprofits develop business plans that are data-driven, actionable, and provide clear pathways for achieving greater impact.

Sarah has more than 20 years of experience helping nonprofit, philanthropic, and government leaders more effectively, efficiently, and strategically scale and achieve greater impact. Across her career in the social sector, Sarah has helped nonprofit and government entities use data, set vision, and identify and establish the resources, systems, and processes needed to achieve growth and change.

Sarah was formerly President of LOCUS Impact Investing, which empowers philanthropists to leverage their assets and use innovative financing tools for community economic development. Previously, Sarah was an Associate Managing Director at Arabella Advisors, developing, incubating, launching, and providing operational infrastructure to hundreds of charitable initiatives.

🇺🇸 = Veteran

🦅 = US Government Service

❤️ = Nonprofit Service