Psychologist Peter Gray argues that modern societies have dramatically reduced children's opportunities for independent, self-directed play, replacing it with constant adult supervision, structured activities, and academic pressure. Drawing on anthropological work with hunter-gatherer societies, his own research, and personal stories, he explains how free, age-mixed play builds social skills, problem solving, independence, and psychological resilience, and links the loss of such play to rising anxiety and depression in young people. He and host Shankar Vedantam also discuss practical ways for parents, schools, and communities to restore more autonomy and unstructured play to children's lives.