Complexity is the defining characteristic of 21st century social and environmental problems. From climate change to racial inequity to the decline of liberal democracy, today’s challenges are systemic, interconnected, deeply entrenched, and poorly understood. Decades of work and investment has failed to eliminate them: Carbon emissions continue to rise, race continues to predict a variety of life outcomes, and authoritarianism is gaining traction around the world. Yet too often funders and nonprofits search for silver bullet solutions to these issues. We believe there are no easy answers to complex problems: Addressing them requires bold new ideas, a commitment to continuous learning and adaptation, merging solutions from those on the ground with those who have a birds-eye view, and collaboration across organizations, sectors, and disciplines.