This review paper aims to present the phenomenon of parentification, its determinants and outcomes. Parentification is usually defined as a reversal of family roles, when a child assumes the role of a parent and the parent takes on the role of a child. Parentification occurs when a parent partially, or entirely abdicates his, or her parental tasks and duties. The parent’s abdication sets in motion the process of parentification, in which a child, usually the eldest in the family, feels obliged to take on the role of a parent in various spheres of family life. The care and duties rendered by the child can be instrumental, or emotional in character. The parentified child may suffer various costs and his, or her correct development may be endangered. Although the results of many international and the few Polish studies indicate that parentification is a very complex and multi-faceted phenomenon, they often point out both the immediate and long term consequences of the reversal of roles in the family.