About Us
At Castilla Impact, we partner with nonprofits, fiscal sponsors, philanthropic families, institutional donors, and corporate philanthropy teams to navigate today’s complex legal, regulatory, and operational landscape.
Led by a seasoned nonprofit tax lawyer, former private foundation general counsel, and former managing director for a leading philanthropic and nonprofit consulting firm, we bring a rare combination of legal acumen, operational expertise, and insider philanthropic knowledge to help mission-driven organizations reduce risk, unlock potential, and drive impact.
Our Core Values
Collaborative Partnership
We believe the best solutions come from working with you, not just for you.
Creative Thinking
We approach every challenge with imagination, curiosity, and a hunger for innovative solutions.
Strategic Focus
We ground our work in smart, actionable strategies that deliver meaningful outcomes.
Resilience + Sustainability
We help build organizations designed not only to succeed today, but thrive long into the future.
Purpose-Driven Impact
We are driven by a bold mission: to help visionary leaders spark transformative change that endures.
About Isaiah
Isaiah most recently served as a Managing Director in the Washington, DC office of Arabella Advisors from 2020-2025. At Arabella, Isaiah partnered with changemakers to advance social change. Isaiah takes great pride in partnering with those who want to turn ambitious ideas into programs and projects that are movement-driven and oriented towards long-term, world-changing impact. Isaiah’s expertise combines his experience as a general counsel with the drive and persistence he exhibited on the campaign trail.
For over four years, Isaiah was general counsel and secretary at Democracy Fund, a private foundation working to protect and strengthen US democracy, and its affiliated (c)(4), Democracy Fund Voice. As general counsel, Isaiah aimed to be more than “the lawyer.” He was a thought partner, a problem-solver, and a doer. He provided legal and strategic guidance for the foundation’s program development, compliance approach, strategic direction, and grant-making processes.
Prior to his time at DF and DFV, Isaiah was counsel for the Bolder Advocacy Program at Alliance for Justice. At AFJ, he coached nonprofits on strategies to maximize their advocacy capacity.
Isaiah also served as Deputy Finance Director for the Ronnie Musgrove for United States Senate campaign, North Regional Finance Director for the Alex Sink for Governor campaign in Florida, and Finance Director and Counsel for Progress for Mississippi PAC and Bill Luckett for Mississippi gubernatorial campaign. Isaiah holds a Bachelor of Arts in music from Tougaloo College and a Doctor of Jurisprudence from Mississippi College School of Law.
