Perinatal mental health is a vital component of public mental health. The perinatal period represents the time in a woman’s life when she is at the highest risk of developing new-onset psychiatric disorders or relapse of an existing mental illness. Optimisation of maternal mental health in the perinatal period is associated with both short- and long-term benefits not only for the mother, but also for her infant and family. However, perinatal mental health service provision remains variable across the world. At present in Northern Ireland, 80% of women do not have access to specialist community perinatal mental health services, and without access to a mother and baby unit, mothers who require a psychiatric admission in the postnatal period are separated from their baby. However, following successful campaigns, funding for development of specialist perinatal mental health community teams has recently been approved. In this article, we discuss the importance of perinatal mental health from a public health perspective and explore challenges and opportunities in the ongoing journey of specialist service development in Northern Ireland.