This report provides a summary of Healthy Development Summit II: Changing frames and expanding partnerships to promote children’s mental health and social/emotional wellbeing. The Summit assembled a diverse group of stakeholders together to generate ideas for new ways to move forward to promote young children’s positive mental health. The second of two summits, this summit focused on the application of the research to practice and policy across sectors of society; that is using what we know to inform what we do. As with the first summit, this Summit focused on early childhood (birth to age eight) because the science is very solid in early childhood development. The Summit also built on momentum for change from the Patient Protection and Affordable Care Act3 (2010), which has multiple components related to prevention and positive mental health that may provide new opportunities for promoting young children’s mental health. Finally, the Summit built on heightened public interest in mental health, particularly in young people, due to media and policymakers’ attention to school violence, bullying, and youth suicide.