The period of pregnancy and the first year after birth, the so-called peripartum period, is a time of upheaval and new demands for expectant mothers and fathers, and thus represents a particularly vulnerable phase. Mental health disorders are among the most common health problems during this phase of life. For appropriate psychotherapy, in addition to disorder-specific approaches, the specific challenges faced by expectant parents must also be considered. This volume provides a comprehensive understanding of these challenges and outlines practical approaches. The first part discusses, taking into account current scientific findings, key psychologically relevant factors in the transition to parenthood. These include, among other things, changes in identity and on a physiological level, societal ideals and role models, and the couple's relationship. Queer parents are explicitly included in the discussion.