This grant provides funds to the Science Festival Alliance (SFA)—a network and incubator of science festivals across the country—to promote the development and expansion of 12 science festivals across the United States in communities with small resource bases and with a focus on promoting diversity. SFA will select and recruit four leading festivals; they will spend the first year experimenting with different approaches to improving diversity. Each lead festival would create a customized plan for engaging diverse audiences with measurable indicators for progress that would be evaluated after 12 months. This new knowledge would then be applied in selecting the 12 new partners—each lead festival is responsible for recruiting and mentoring three new festival partners in communities with small resource bases. The 12 selected festivals would be given modest $2,000 professional development grants and then be eligible for $10,000 challenge grants as they develop their own plans. Grant funds support these activities and associated administrative and operational costs.