The Wallace Foundation's Partnerships for Social and Emotional Learning Initiative (PSELI) is a six-year initiative that The Wallace Foundation launched in 2017 to explore whether and how children benefit when schools and their out-of-school-time programs partner to improve social and emotional learning (SEL), as well as what it takes to do this work. The six communities that participate in PSELI are Boston, Massachusetts; Dallas, Texas; Denver, Colorado; Palm Beach County, Florida; Tacoma, Washington; and Tulsa, Oklahoma. According to the Collaborative for Academic and Social and Emotional Learning, SEL is "the process through which children and adults understand and manage emotions, set and achieve positive goals, feel and show empathy for others, establish and maintain positive relationships, and make responsible decisions." Six case studies spotlight specific approaches to implementing SEL. This cross-cutting report briefly summarizes each case and highlights shared themes among them. Themes include implementing SEL by building adults' SEL skills before building children's SEL skills and sustaining SEL work even as staff turn over by distributing leadership. [For an earlier report on this initiative, "Early Lessons from Schools and Out-of-School Time Programs Implementing Social and Emotional Learning. Lessons from the Partnerships for Social and Emotional Learning Initiative. Volume 1. Research Report. RR-A379-1," see ED609418. For the six case study reports, see ED623578, ED623579, ED623580, ED623581, ED623582, and ED623583.]