Although official figures on the phenomenon are lacking, it is clear that children arriving in the European Union (EU) are often accompanied by persons other than their parents or guardians. Such children are usually referred to as ‘separated’ children. Their identification and registration bring additional challenges, and their protection needs are often neglected. On arrival, these children are often ‘accompanied’, but the accompanying adult(s) may not necessarily be able, or suitable, to assume responsibility for their care. These children are also at risk of exploitation and abuse, or may already be victims. Their realities and special needs require additional attention. The lack of data and guidance on separated children poses a serious challenge. This focus section outlines the specific protection needs of separated children, and highlights current responses and promising practices among EU Member States.