This first book of a two-volume series describes current research and state of the art clinical practice the shed light on the developmental origins of psychopathology in the first year of life, i.e. approximately up to the emergence of secondary intersubjectivity and/or walking. The second volume explores the interactional underpinnings of psychopathology in toddlerhood, from the time of voluntarily gross motor functioning to the emergence and basic organization of symbolic language at 24-30 months. A comprehensive approach is adopted, focusing on the fundamentally interactive nature of early development and examining interactions both with caregivers and more broadly with the socio-cultural environment. The books describe the processes involved in psychopathological trajectories and provide clinical insight into tailored, culturally sensitive therapeutic care in diverse environments. This volume discusses in detail situations placing the infant at risk and the nature of infant development, including communication, intersubjectivity, functional development, and affective and emotional development. Culturally and socially sensitive approaches to psychopathology are examined, with examples of specific infant- and family-centered therapies. Information on risk of abuse and neglect and infant protection policies is included.