Collective action is an effective way for nonprofits to increase their impact, but key capacities are needed to enable these types of partnerships to thrive. This publication offers insights on the core capacities nonprofits need to collaborate and how funders can help. Achieving real and lasting impact on the issues we care about often means changing complex and dynamic systems. We know that no single organization can succeed in this work on its own. When people reach across the lines that too often divide organizations and sectors, they tap into new ideas and new resources and create new partnerships that can help them achieve their goals.