Challenges to hearing health are a significant public health problem. At least ten million Americans have a hearing loss that interferes with the understanding of normal speech. If lesser degrees of loss are included, the number rises to 28 million. Although there have been considerable advances in understanding the etiology of hearing loss, with genetic causes now thought to account for up to 50% of congenital losses, in many individual cases, the cause of hearing loss remains unknown. This lack of knowledge of the basic pathophysiology of hearing difficulties hampers prevention and treatment efforts. Growing interest in life course theory has led to suggestions that it could prove useful to apply a life course lens to the study of hearing loss, and of hearing health, throughout the life span. In this paper we consider the implications of the Life Course Health Development model for understanding the mechanisms, pathways, and determinants of hearing ability. We consider the implications of early hearing loss for health development over the life course and the factors through the life course that contribute to hearing ability in adult life. We consider the concept not just of hearing loss but of “hearing health” and how to achieve it, the research priorities that are suggested by this review, and the implications for policy and practice.