This handbook examines the psychology of fatherhood throughout the lifespan and across multiple contexts. It synthesizes the trajectory of research and theorization of fathering that has traditionally dominated fatherhood literature. The book explores fathering within the developmental stages of children, from infancy to adulthood. In addition, it addresses the health and well-being of fathers from the perinatal period onward, with a focus on isolation, loss, trauma, and mental and physical health. The book emphasizes positive fatherhood and masculinity, thereby offering new perspectives of fatherhood. It synthesizes cutting-edge research on the intersectionality of fathering and provides knowledge of fatherhood for diverse populations, including military, LGBTQ, and fathers on the margins. The handbook reviews clinical assessment as well as community-based prevention and intervention strategies for issues of fatherhood and examines directions for future public policy and on-the-ground work. It offers recommendations for promoting the health and well-being of fathers and their families from multiple perspectives. Key areas of coverage include: Historical, multicultural, and future directions in the research of fatherhood. Fatherhood and child development, from infancy to emerging adulthood. Grandfathering and adult children. Fatherhood and men's mental and physical health and well-being. Positive masculinity and fatherhood. The Handbook of the Psychology of Fatherhood is an invaluable resource for researchers, clinicians and practitioners, and policy advocates as well as graduate students in developmental psychology, social work, public health, pediatrics, human development, family studies, child and adolescent psychiatry, school and educational psychology, and all interrelated disciplines.