Mosaic is a new national grantmaking initiative strengthening the movement infrastructure that supports people working to ensure clean air and water, a safe climate, healthy and just communities, and thriving natural systems. Movement infrastructure-field-wide connections and shared tools, like communications, leadership development, data & information, advocacy tools and training, and relationships & trust-is instrumental to the success of all social movements. Mosaic is the result of a two-year design process with diverse activists and organizations that determined that strengthening movement infrastructure is crucial if we are to meet the pace and scale of today's environmental challenges.