This article investigates research on early childhood development and on both listening to music and participation in music activities by young children. Research is reviewed that explores possible relationships between various music-related experiences and cognitive development, from the "Mozart Effect" studies to participation in piano lessons or other music training over time. This literature review suggest that, just as a high quality early childhood educational environment can positively affect child development, the same may be true of a music experience that is developmentally responsive and sequenced in complexity.