Section 1, Developmental Affective Neuroscience, provides an overview for the book (e.g., regulation theory, perspectives from others on the topic). The concept of self-regulatory systems is introduced and applied to brain development. Indubitably, the development of the infant’s brain occurs in the context of a relationship with another self (e.g., the mother). Thus, a central theme is the experience-dependent relationship between infant and mother for the development of self-regulatory processes. The work of Bowlby and others on attachment is integrated with neurobiological findings. In particular, the function of the right prefrontal cortex, parent-infant communication, and attachment disorders are discussed in detail. When available, functional magnetic resonance imaging findings are included. Section 2, Developmental Neuropsychiatry, discusses predispositions to psychiatric disorders. Separate chapters review how brain development, affect regulation, and health might be affected by 1) a secure attachment, 2) relational trauma, and 3) eventual affect dysregulation.