In recent years, philanthropy has been grappling with calls for increased transparency and more inclusive processes when it comes to making decisions about the best use of its resources. Some foundations have responded by focusing on listening, experimenting with participatory grantmaking, and exploring what it means to center equity in their work. Despite such promising efforts, foundation evaluation and learning practices largely remain unchanged. That is, foundations continue to roll out evaluations in the traditional way: funders craft requests for proposals with limited consultation from others, evaluators develop their approaches in silos, and one design is selected for implementation. The needs of foundations often take precedence over those of others with potential to benefit. This learning brief is about the possibility of what can happen when more voices are included in the process of evaluation design. It tells the story of how Engage R+D partnered with the Bill & Melinda Gates Foundation to apply a creative, participatory technique—known as a design charrette—to engage a broad variety of stakeholders in collaboratively designing a summative evaluation of Networks for School Improvement, one of the Foundation's signature K-12 investments.