This multidisciplinary volume features many of the world’s leading experts of infant development, who synthesize their research on infant learning and behaviour, while integrating perspectives across neuroscience, socio-cultural context, and policy. It offers an unparalleled overview of infant development across foundational areas such as prenatal development, brain development, epigenetics, physical growth, nutrition, cognition, language, attachment, and risk. The chapters present theoretical and empirical depth and rigor across specific domains of development, while highlighting reciprocal connections among brain, behavior, and social-cultural context. The handbook simultaneously educates, enriches, and encourages. It educates through detailed reviews of innovative methods and empirical foundations and enriches by considering the contexts of brain, culture, and policy. This cutting-edge volume establishes an agenda for future research and policy, and highlights research findings and application for advanced students, researchers, practitioners, and policy-makers with interests in understanding and promoting infant development.