Mental health problems during and immediately after pregnancy are a major concern across the world. As well as affecting the health of the mother, they can have significant, harmful, and long term effects on the infant if not dealt with effectively. Perinatal Psychiatry honours the work of Channi Kumar, one of the seminal figures in the history of perinatal psychiatry, and presents a comprehensive multidisciplinary review of the field. Bringing together the leading researchers in the area, it covers the causes of perinatal mental health problems, the biology of perinatal depression and its more extreme form, puerperal psychosis, as well as psychosocial and psychological interventions, hormonal and neural substrates of perinatal depression, and risk factors and epidemiology.