Between 2015 and 2017, almost one million asylum-seeking children registered in the European Union, and 200 000 of these arrived unaccompanied by a caregiver. These children faced particular risks, including being exposed to discrimination, marginalization, institutionalization and exclusion. When considering health and health care interventions for migrant children, some areas need specific attention, such as their diverse backgrounds, whether they are unaccompanied and separated from family, whether they have been trafficked and also if they are children who have been left behind. Policy considerations include an intersectoral approach to promote good health and well-being, particularly mental health, in migrant children that target risk factors at the individual, family and community levels. Particular emphasis is placed on how national/local governments have an important role in fostering or hindering living conditions for refugee and migrant children in the areas of housing, health care services and education.