Early childhood experience is a social determinant of children's health and well-being. The well-being of young children is founded on their relationships and interactions with parents and family members in the home, caregivers, and teachers in early education, and friends and families in the greater community. Unfortunately, the early language experience of infants and toddlers from low-income families is typically vastly different than children from middle- and higher-income families. Hart and Risley (Meaningful differences in the everyday experience of young American children. Brookes, Baltimore, 1995) described a "30 Million Word Gap" experienced by age four for children from poor families compared to economically advantaged families as measured by the number of words delivered by adults in the home to their children. This discrepancy between groups is associated with a deficit in vocabulary growth over time (Hart and Risley in Meaningful differences in the everyday experience of young American children. Brookes, Baltimore, 1995; in The social world of children learning to talk. Brookes, Baltimore, MD, 1999; in Am Educ (Spring), 1-9. http://isites.harvard.edu/fs/docs/icb.topic1317532.files/09-10/Hart-Risley-2003.pdf , 2003), and readiness when they enter preschool and kindergarten compared to their more advantaged classmates. The purpose of this paper is to conceptualize a population-level public health prevention approach to research addressing the harmful impacts of the Word Gap. The approach includes use of evidence-based practices to improve children's language environments to foster their early language and literacy learning in early childhood. After a brief review of the Word Gap, we discuss four aspects: a conceptual framework, a community leadership team as driver of the local intervention, evidence-based language interventions for reducing the gap and promoting child language, and the measurements needed. Implications are discussed.